Issue #1829 - Revert "Issue #1751 -- Remove XP_MACOSX conditionals from /dom"

This reverts commit 0dd3424f774954627d6f53df9fb47379d9b5c871.

71 files changed, 5355 insertions, 105 deletions

diff --git a/dom/base/Navigator.cpp b/dom/base/Navigator.cpp
index 5ad763af76..096f9794a9 100644
--- a/dom/base/Navigator.cpp
+++ b/dom/base/Navigator.cpp
@@ -1393,6 +1393,12 @@ Navigator::GetPlatform(nsAString& aPlatform, bool aUsePrefOverriddenValue)
   aPlatform.AssignLiteral("Win64");
 #elif defined(WIN32)
   aPlatform.AssignLiteral("Win32");
+#elif defined(XP_MACOSX) && defined(__ppc__)
+  aPlatform.AssignLiteral("MacPPC");
+#elif defined(XP_MACOSX) && defined(__i386__)
+  aPlatform.AssignLiteral("MacIntel");
+#elif defined(XP_MACOSX) && defined(__x86_64__)
+  aPlatform.AssignLiteral("MacIntel");
 #else
   // XXX Communicator uses compiled-in build-time string defines
   // to indicate the platform it was compiled *for*, not what it is
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 657c0c0fb2..fa8ba6d97d 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -6840,6 +6840,10 @@ nsContentUtils::HaveEqualPrincipals(nsIDocument* aDoc1, nsIDocument* aDoc2)
 bool
 nsContentUtils::HasPluginWithUncontrolledEventDispatch(nsIContent* aContent)
 {
+#ifdef XP_MACOSX
+  // We control dispatch to all mac plugins.
+  return false;
+#else
   if (!aContent || !aContent->IsInUncomposedDoc()) {
     return false;
   }
@@ -6862,6 +6866,7 @@ nsContentUtils::HasPluginWithUncontrolledEventDispatch(nsIContent* aContent)
   }
 
   return !isWindowless;
+#endif
 }
 
 /* static */
diff --git a/dom/base/nsFocusManager.cpp b/dom/base/nsFocusManager.cpp
index 0c12103fba..6cc5bbd36f 100644
--- a/dom/base/nsFocusManager.cpp
+++ b/dom/base/nsFocusManager.cpp
@@ -64,7 +64,9 @@
 #include "nsAccessibilityService.h"
 #endif
 
+#ifndef XP_MACOSX
 #include "nsIScriptError.h"
+#endif
 
 using namespace mozilla;
 using namespace mozilla::dom;
@@ -1264,10 +1266,12 @@ nsFocusManager::SetFocusInner(nsIContent* aNewContent, int32_t aFlags,
     }
   }
 
-  // Exit fullscreen if we're focusing a windowed plugin. We don't control
-  // event dispatch to windowed plugins, so we can't display the <Press ESC
-  // to leave fullscreen mode> warning on key input if a windowed plugin is
-  // focused, so just exit fullscreen to guard against phishing.
+  // Exit fullscreen if we're focusing a windowed plugin on a non-MacOSX
+  // system. We don't control event dispatch to windowed plugins on non-MacOSX,
+  // so we can't display the "Press ESC to leave fullscreen mode" warning on
+  // key input if a windowed plugin is focused, so just exit fullscreen
+  // to guard against phishing.
+#ifndef XP_MACOSX
   if (contentToFocus &&
       nsContentUtils::
         GetRootDocument(contentToFocus->OwnerDoc())->GetFullscreenElement() &&
@@ -1279,6 +1283,7 @@ nsFocusManager::SetFocusInner(nsIContent* aNewContent, int32_t aFlags,
                                     "FocusedWindowedPluginWhileFullscreen");
     nsIDocument::AsyncExitFullscreen(contentToFocus->OwnerDoc());
   }
+#endif
 
   // if the FLAG_NOSWITCHFRAME flag is used, only allow the focus to be
   // shifted away from the current element if the new shell to focus is
diff --git a/dom/base/nsGlobalWindow.cpp b/dom/base/nsGlobalWindow.cpp
index ccfbf488d3..c6b35a9bf0 100644
--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -6222,7 +6222,18 @@ nsGlobalWindow::CheckSecurityLeftAndTop(int32_t* aLeft, int32_t* aTop, bool aCal
       screen->GetAvailLeft(&screenLeft);
       screen->GetAvailWidth(&screenWidth);
       screen->GetAvailHeight(&screenHeight);
+#if defined(XP_MACOSX)
+      /* The mac's coordinate system is different from the assumed Windows'
+         system. It offsets by the height of the menubar so that a window
+         placed at (0,0) will be entirely visible. Unfortunately that
+         correction is made elsewhere (in Widget) and the meaning of
+         the Avail... coordinates is overloaded. Here we allow a window
+         to be placed at (0,0) because it does make sense to do so.
+      */
+      screen->GetTop(&screenTop);
+#else
       screen->GetAvailTop(&screenTop);
+#endif
 
       if (aLeft) {
         if (screenLeft+screenWidth < *aLeft+winWidth)
@@ -7060,6 +7071,16 @@ nsGlobalWindow::Dump(const nsAString& aStr)
 
   char *cstr = ToNewUTF8String(aStr);
 
+#if defined(XP_MACOSX)
+  // have to convert \r to \n so that printing to the console works
+  char *c = cstr, *cEnd = cstr + strlen(cstr);
+  while (c < cEnd) {
+    if (*c == '\r')
+      *c = '\n';
+    c++;
+  }
+#endif
+
   if (cstr) {
     MOZ_LOG(nsContentUtils::DOMDumpLog(), LogLevel::Debug, ("[Window.Dump] %s", cstr));
 #ifdef XP_WIN
diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index 15448181f7..5229948e01 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -59,6 +59,10 @@
 
 #include "nsJSPrincipals.h"
 
+#ifdef XP_MACOSX
+// AssertMacros.h defines 'check' and conflicts with AccessCheck.h
+#undef check
+#endif
 #include "AccessCheck.h"
 
 #include "mozilla/Logging.h"
diff --git a/dom/base/nsObjectLoadingContent.cpp b/dom/base/nsObjectLoadingContent.cpp
index f8541c61ba..4129135baa 100644
--- a/dom/base/nsObjectLoadingContent.cpp
+++ b/dom/base/nsObjectLoadingContent.cpp
@@ -95,6 +95,13 @@
 #endif
 #endif // XP_WIN
 
+#ifdef XP_MACOSX
+// HandlePluginCrashed() and HandlePluginInstantiated() needed from here to
+// fix bug 1147521.  Should later be replaced by proper interface methods,
+// maybe on nsIObjectLoadingContext.
+#include "mozilla/dom/HTMLObjectElement.h"
+#endif
+
 static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
 
 static const char *kPrefJavaMIME = "plugin.java.mime";
@@ -909,6 +916,10 @@ nsObjectLoadingContent::InstantiatePluginInstance(bool aIsLoading)
                             NS_LITERAL_STRING("PluginInstantiated"));
   NS_DispatchToCurrentThread(ev);
 
+#ifdef XP_MACOSX
+  HTMLObjectElement::HandlePluginInstantiated(thisContent->AsElement());
+#endif
+
   return NS_OK;
 }
 
@@ -2907,6 +2918,10 @@ nsObjectLoadingContent::PluginCrashed(nsIPluginTag* aPluginTag,
   nsCOMPtr<nsIContent> thisContent =
     do_QueryInterface(static_cast<nsIImageLoadingContent*>(this));
 
+#ifdef XP_MACOSX
+  HTMLObjectElement::HandlePluginCrashed(thisContent->AsElement());
+#endif
+
   PluginDestroyed();
 
   // Switch to fallback/crashed state, notify
@@ -3145,6 +3160,10 @@ nsObjectLoadingContent::DoStopPlugin(nsPluginInstanceOwner* aInstanceOwner,
       return;
     }
 
+#if defined(XP_MACOSX)
+    aInstanceOwner->HidePluginWindow();
+#endif
+
     RefPtr<nsPluginHost> pluginHost = nsPluginHost::GetInst();
     NS_ASSERTION(pluginHost, "No plugin host?");
     pluginHost->StopPluginInstance(inst);
diff --git a/dom/base/nsWindowRoot.cpp b/dom/base/nsWindowRoot.cpp
index 38348b46c2..509420f76d 100644
--- a/dom/base/nsWindowRoot.cpp
+++ b/dom/base/nsWindowRoot.cpp
@@ -34,8 +34,14 @@ nsWindowRoot::nsWindowRoot(nsPIDOMWindowOuter* aWindow)
   mWindow = aWindow;
   MOZ_ASSERT(mWindow->IsOuterWindow());
 
+  // Keyboard indicators are not shown on Mac by default.
+#if defined(XP_MACOSX)
+  mShowAccelerators = false;
+  mShowFocusRings = false;
+#else
   mShowAccelerators = true;
   mShowFocusRings = true;
+#endif
 }
 
 nsWindowRoot::~nsWindowRoot()
diff --git a/dom/canvas/WebGL2Context.cpp b/dom/canvas/WebGL2Context.cpp
index 09891e7b6e..8c472384e5 100644
--- a/dom/canvas/WebGL2Context.cpp
+++ b/dom/canvas/WebGL2Context.cpp
@@ -125,6 +125,13 @@ WebGLContext::InitWebGL2(FailureReason* const out_failReason)
     fnGatherMissing2(gl::GLFeature::occlusion_query_boolean,
                      gl::GLFeature::occlusion_query);
 
+#ifdef XP_MACOSX
+    // On OSX, GL core profile is used. This requires texture swizzle
+    // support to emulate legacy texture formats: ALPHA, LUMINANCE,
+    // and LUMINANCE_ALPHA.
+    fnGatherMissing(gl::GLFeature::texture_swizzle);
+#endif
+
     fnGatherMissing2(gl::GLFeature::prim_restart_fixed,
                      gl::GLFeature::prim_restart);
 
diff --git a/dom/canvas/WebGLBuffer.cpp b/dom/canvas/WebGLBuffer.cpp
index 11d956c8a4..02a8f649fe 100644
--- a/dom/canvas/WebGLBuffer.cpp
+++ b/dom/canvas/WebGLBuffer.cpp
@@ -115,7 +115,7 @@ WebGLBuffer::BufferData(GLenum target, size_t size, const void* data, GLenum usa
     const ScopedLazyBind lazyBind(gl, target, this);
     mContext->InvalidateBufferFetching();
 
-#if defined(MOZ_WIDGET_GTK)
+#if defined(XP_MACOSX) || defined(MOZ_WIDGET_GTK)
     // bug 790879
     if (gl->WorkAroundDriverBugs() &&
         size > INT32_MAX)
diff --git a/dom/canvas/WebGLContext.h b/dom/canvas/WebGLContext.h
index 628d4713ca..0510e6898a 100644
--- a/dom/canvas/WebGLContext.h
+++ b/dom/canvas/WebGLContext.h
@@ -30,6 +30,10 @@
 #include "ScopedGLHelpers.h"
 #include "TexUnpackBlob.h"
 
+#ifdef XP_MACOSX
+#include "ForceDiscreteGPUHelperCGL.h"
+#endif
+
 // Local
 #include "WebGLContextLossHandler.h"
 #include "WebGLContextUnchecked.h"
@@ -2011,6 +2015,15 @@ protected:
     JSObject* WebGLObjectAsJSObject(JSContext* cx, const WebGLObjectType*,
                                     ErrorResult& rv) const;
 
+#ifdef XP_MACOSX
+    // see bug 713305. This RAII helper guarantees that we're on the discrete GPU, during its lifetime
+    // Debouncing note: we don't want to switch GPUs too frequently, so try to not create and destroy
+    // these objects at high frequency. Having WebGLContext's hold one such object seems fine,
+    // because WebGLContext objects only go away during GC, which shouldn't happen too frequently.
+    // If in the future GC becomes much more frequent, we may have to revisit then (maybe use a timer).
+    ForceDiscreteGPUHelperCGL mForceDiscreteGPUHelper;
+#endif
+
 public:
     // console logging helpers
     void GenerateWarning(const char* fmt, ...);
diff --git a/dom/canvas/WebGLContextBuffers.cpp b/dom/canvas/WebGLContextBuffers.cpp
index 6f583c10c6..e787b99143 100644
--- a/dom/canvas/WebGLContextBuffers.cpp
+++ b/dom/canvas/WebGLContextBuffers.cpp
@@ -295,6 +295,16 @@ WebGLContext::BindBufferRange(GLenum target, GLuint index, WebGLBuffer* buffer,
 
     ////
 
+#ifdef XP_MACOSX
+    if (buffer && buffer->Content() == WebGLBuffer::Kind::Undefined &&
+        gl->WorkAroundDriverBugs())
+    {
+        // BindBufferRange will fail if the buffer's contents is undefined.
+        // Bind so driver initializes the buffer.
+        gl->fBindBuffer(target, buffer->mGLName);
+    }
+#endif
+
     gl->fBindBufferRange(target, index, buffer ? buffer->mGLName : 0, offset, size);
 
     ////
@@ -342,6 +352,12 @@ WebGLContext::BufferData(GLenum target, WebGLsizeiptr size, GLenum usage)
     if (!checkedSize.isValid())
       return ErrorOutOfMemory("%s: Size too large for platform.", funcName);
      
+#if defined(XP_MACOSX)
+    if (gl->WorkAroundDriverBugs() && size > 1200000000) {
+      return ErrorOutOfMemory("Allocations larger than 1200000000 fail on MacOS.");
+    }
+#endif
+
     const UniqueBuffer zeroBuffer(calloc(size, 1));
     if (!zeroBuffer)
         return ErrorOutOfMemory("%s: Failed to allocate zeros.", funcName);
diff --git a/dom/canvas/WebGLContextDraw.cpp b/dom/canvas/WebGLContextDraw.cpp
index c0ba20301a..6c684b2ff8 100644
--- a/dom/canvas/WebGLContextDraw.cpp
+++ b/dom/canvas/WebGLContextDraw.cpp
@@ -1045,6 +1045,13 @@ WebGLContext::WhatDoesVertexAttrib0Need() const
     const auto& isAttribArray0Enabled = mBoundVertexArray->mAttribs[0].mEnabled;
 
     bool legacyAttrib0 = gl->IsCompatibilityProfile();
+#ifdef XP_MACOSX
+    if (gl->WorkAroundDriverBugs()) {
+        // Failures in conformance/attribs/gl-disabled-vertex-attrib.
+        // Even in Core profiles on NV. Sigh.
+        legacyAttrib0 |= (gl->Vendor() == gl::GLVendor::NVIDIA);
+    }
+#endif
 
     if (!legacyAttrib0)
         return WebGLVertexAttrib0Status::Default;
diff --git a/dom/canvas/WebGLContextValidate.cpp b/dom/canvas/WebGLContextValidate.cpp
index 60bb3a32cc..30d4c65221 100644
--- a/dom/canvas/WebGLContextValidate.cpp
+++ b/dom/canvas/WebGLContextValidate.cpp
@@ -695,6 +695,18 @@ WebGLContext::InitAndValidateGL(FailureReason* const out_failReason)
         gl->fEnable(LOCAL_GL_PROGRAM_POINT_SIZE);
     }
 
+#ifdef XP_MACOSX
+    if (gl->WorkAroundDriverBugs() &&
+        gl->Vendor() == gl::GLVendor::ATI &&
+        !nsCocoaFeatures::IsAtLeastVersion(10,9))
+    {
+        // The Mac ATI driver, in all known OSX version up to and including
+        // 10.8, renders points sprites upside-down. (Apple bug 11778921)
+        gl->fPointParameterf(LOCAL_GL_POINT_SPRITE_COORD_ORIGIN,
+                             LOCAL_GL_LOWER_LEFT);
+    }
+#endif
+
     if (gl->IsSupported(gl::GLFeature::seamless_cube_map_opt_in)) {
         gl->fEnable(LOCAL_GL_TEXTURE_CUBE_MAP_SEAMLESS);
     }
diff --git a/dom/canvas/WebGLProgram.cpp b/dom/canvas/WebGLProgram.cpp
index 1ff27e1d2f..9b204358bb 100644
--- a/dom/canvas/WebGLProgram.cpp
+++ b/dom/canvas/WebGLProgram.cpp
@@ -689,6 +689,24 @@ WebGLProgram::GetFragDataLocation(const nsAString& userName_wide) const
     gl->MakeCurrent();
 
     const NS_LossyConvertUTF16toASCII userName(userName_wide);
+#ifdef XP_MACOSX
+    if (gl->WorkAroundDriverBugs()) {
+        // OSX doesn't return locs for indexed names, just the base names.
+        // Indicated by failure in: conformance2/programs/gl-get-frag-data-location.html
+        bool isArray;
+        size_t arrayIndex;
+        nsCString baseUserName;
+        if (!ParseName(userName, &baseUserName, &isArray, &arrayIndex))
+            return -1;
+
+        if (arrayIndex >= mContext->mImplMaxDrawBuffers)
+            return -1;
+
+        const auto baseLoc = GetFragDataByUserName(this, baseUserName);
+        const auto loc = baseLoc + GLint(arrayIndex);
+        return loc;
+    }
+#endif
     return GetFragDataByUserName(this, userName);
 }
 
@@ -752,6 +770,11 @@ WebGLProgram::GetProgramParameter(GLenum pname) const
         return JS::BooleanValue(IsLinked());
 
     case LOCAL_GL_VALIDATE_STATUS:
+#ifdef XP_MACOSX
+        // See comment in ValidateProgram.
+        if (gl->WorkAroundDriverBugs())
+            return JS::BooleanValue(true);
+#endif
         // Todo: Implement this in our code.
         return JS::BooleanValue(bool(GetProgramiv(gl, mGLName, pname)));
 
@@ -1354,6 +1377,17 @@ WebGLProgram::ValidateProgram() const
 {
     mContext->MakeContextCurrent();
     gl::GLContext* gl = mContext->gl;
+
+#ifdef XP_MACOSX
+    // See bug 593867 for NVIDIA and bug 657201 for ATI. The latter is confirmed
+    // with Mac OS 10.6.7.
+    if (gl->WorkAroundDriverBugs()) {
+        mContext->GenerateWarning("validateProgram: Implemented as a no-op on"
+                                  " Mac to work around crashes.");
+        return;
+    }
+#endif
+
     gl->fValidateProgram(mGLName);
 }
 
diff --git a/dom/canvas/WebGLShaderValidator.cpp b/dom/canvas/WebGLShaderValidator.cpp
index eadeeb56b0..bf2df82f71 100644
--- a/dom/canvas/WebGLShaderValidator.cpp
+++ b/dom/canvas/WebGLShaderValidator.cpp
@@ -63,8 +63,34 @@ ChooseValidatorCompileOptions(const ShBuiltInResources& resources,
                SH_REGENERATE_STRUCT_NAMES;
     }
 
-    // We want to do this everywhere.
+#ifndef XP_MACOSX
+    // We want to do this everywhere, but to do this on Mac, we need
+    // to do it only on Mac OSX > 10.6 as this causes the shader
+    // compiler in 10.6 to crash
     options |= SH_CLAMP_INDIRECT_ARRAY_BOUNDS;
+#endif
+
+#ifdef XP_MACOSX
+    if (gl->WorkAroundDriverBugs()) {
+        // Work around https://bugs.webkit.org/show_bug.cgi?id=124684,
+        // https://chromium.googlesource.com/angle/angle/+/5e70cf9d0b1bb
+        options |= SH_UNFOLD_SHORT_CIRCUIT;
+        
+        // OS X 10.7/10.8 specific:
+        
+        // Work around bug 665578 and bug 769810
+        if (gl->Vendor() == gl::GLVendor::ATI) {
+            options |= SH_EMULATE_BUILT_IN_FUNCTIONS;
+        }
+        // Work around bug 735560
+        if (gl->Vendor() == gl::GLVendor::Intel) {
+            options |= SH_EMULATE_BUILT_IN_FUNCTIONS;
+        }
+
+        // Work around that Mac drivers handle struct scopes incorrectly.
+        options |= SH_REGENERATE_STRUCT_NAMES;
+    }
+#endif
 
     if (resources.MaxExpressionComplexity > 0) {
         options |= SH_LIMIT_EXPRESSION_COMPLEXITY;
@@ -161,6 +187,15 @@ WebGLContext::CreateShaderValidator(GLenum shaderType) const
     // If underlying GLES doesn't have highp in frag shaders, it should complain anyways.
     resources.FragmentPrecisionHigh = mDisableFragHighP ? 0 : 1;
 
+    if (gl->WorkAroundDriverBugs()) {
+#ifdef XP_MACOSX
+        if (gl->Vendor() == gl::GLVendor::NVIDIA) {
+            // Work around bug 890432
+            resources.MaxExpressionComplexity = 1000;
+        }
+#endif
+    }
+
     int compileOptions = webgl::ChooseValidatorCompileOptions(resources, gl);
     return webgl::ShaderValidator::Create(shaderType, spec, outputLanguage, resources,
                                           compileOptions);
diff --git a/dom/events/EventStateManager.cpp b/dom/events/EventStateManager.cpp
index 86201bdc30..9f06deb2ba 100644
--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -93,6 +93,10 @@
 #include "Units.h"
 #include "mozilla/layers/APZCTreeManager.h"
 
+#ifdef XP_MACOSX
+#import <ApplicationServices/ApplicationServices.h>
+#endif
+
 namespace mozilla {
 
 using namespace dom;
@@ -1511,6 +1515,14 @@ EventStateManager::FireContextClick()
     return;
   }
 
+#ifdef XP_MACOSX
+  // Hack to ensure that we don't show a context menu when the user
+  // let go of the mouse after a long cpu-hogging operation prevented
+  // us from handling any OS events. See bug 117589.
+  if (!CGEventSourceButtonState(kCGEventSourceStateCombinedSessionState, kCGMouseButtonLeft))
+    return;
+#endif
+
   nsEventStatus status = nsEventStatus_eIgnore;
 
   // Dispatch to the DOM. We have to fake out the ESM and tell it that the
@@ -2823,6 +2835,29 @@ EventStateManager::DecideGestureEvent(WidgetGestureNotifyEvent* aEvent,
   aEvent->mPanDirection = panDirection;
 }
 
+#ifdef XP_MACOSX
+static bool
+NodeAllowsClickThrough(nsINode* aNode)
+{
+  while (aNode) {
+    if (aNode->IsXULElement()) {
+      mozilla::dom::Element* element = aNode->AsElement();
+      static nsIContent::AttrValuesArray strings[] =
+        {&nsGkAtoms::always, &nsGkAtoms::never, nullptr};
+      switch (element->FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::clickthrough,
+                                       strings, eCaseMatters)) {
+        case 0:
+          return true;
+        case 1:
+          return false;
+      }
+    }
+    aNode = nsContentUtils::GetCrossDocParentNode(aNode);
+  }
+  return true;
+}
+#endif
+
 void
 EventStateManager::PostHandleKeyboardEvent(WidgetKeyboardEvent* aKeyboardEvent,
                                            nsEventStatus& aStatus,
@@ -3055,7 +3090,10 @@ EventStateManager::PostHandleEvent(nsPresContext* aPresContext,
             // focused frame
             EnsureDocument(mPresContext);
             if (mDocument) {
-              fm->ClearFocus(mDocument->GetWindow());
+#ifdef XP_MACOSX
+              if (!activeContent || !activeContent->IsXULElement())
+#endif
+                fm->ClearFocus(mDocument->GetWindow());
               fm->SetFocusedWindow(mDocument->GetWindow());
             }
           }
@@ -3467,6 +3505,18 @@ EventStateManager::PostHandleEvent(nsPresContext* aPresContext,
     }
     break;
 
+#ifdef XP_MACOSX
+  case eMouseActivate:
+    if (mCurrentTarget) {
+      nsCOMPtr<nsIContent> targetContent;
+      mCurrentTarget->GetContentForEvent(aEvent, getter_AddRefs(targetContent));
+      if (!NodeAllowsClickThrough(targetContent)) {
+        *aStatus = nsEventStatus_eConsumeNoDefault;
+      }
+    }
+    break;
+#endif
+
   default:
     break;
   }
diff --git a/dom/events/TextComposition.cpp b/dom/events/TextComposition.cpp
index 3b3dc6505b..bd7ebbc468 100644
--- a/dom/events/TextComposition.cpp
+++ b/dom/events/TextComposition.cpp
@@ -21,8 +21,21 @@
 #include "mozilla/Unused.h"
 #include "mozilla/dom/TabParent.h"
 
+#ifdef XP_MACOSX
+// Some defiens will be conflict with OSX SDK
+#define TextRange _TextRange
+#define TextRangeArray _TextRangeArray
+#define Comment _Comment
+#endif
+
 #include "nsPluginInstanceOwner.h"
 
+#ifdef XP_MACOSX
+#undef TextRange
+#undef TextRangeArray
+#undef Comment
+#endif
+
 using namespace mozilla::widget;
 
 namespace mozilla {
diff --git a/dom/html/HTMLButtonElement.cpp b/dom/html/HTMLButtonElement.cpp
index 80df5bc740..e493d1891d 100644
--- a/dom/html/HTMLButtonElement.cpp
+++ b/dom/html/HTMLButtonElement.cpp
@@ -156,7 +156,11 @@ HTMLButtonElement::IsHTMLFocusable(bool aWithMouse, bool *aIsFocusable, int32_t
     return true;
   }
 
-  *aIsFocusable = !IsDisabled();
+  *aIsFocusable = 
+#ifdef XP_MACOSX
+    (!aWithMouse || nsFocusManager::sMouseFocusesFormControl) &&
+#endif
+    !IsDisabled();
 
   return false;
 }
diff --git a/dom/html/HTMLImageElement.cpp b/dom/html/HTMLImageElement.cpp
index cb586d68ac..5e75d09349 100644
--- a/dom/html/HTMLImageElement.cpp
+++ b/dom/html/HTMLImageElement.cpp
@@ -599,6 +599,9 @@ HTMLImageElement::IsHTMLFocusable(bool aWithMouse,
   }
 
   *aIsFocusable =
+#ifdef XP_MACOSX
+    (!aWithMouse || nsFocusManager::sMouseFocusesFormControl) &&
+#endif
     (tabIndex >= 0 || HasAttr(kNameSpaceID_None, nsGkAtoms::tabindex));
 
   return false;
diff --git a/dom/html/HTMLInputElement.cpp b/dom/html/HTMLInputElement.cpp
index 866a5ac8c5..d9f745d4ca 100644
--- a/dom/html/HTMLInputElement.cpp
+++ b/dom/html/HTMLInputElement.cpp
@@ -3566,6 +3566,7 @@ HTMLInputElement::Focus(ErrorResult& aError)
   return;
 }
 
+#if !defined(XP_MACOSX)
 bool
 HTMLInputElement::IsNodeApzAwareInternal() const
 {
@@ -3574,6 +3575,7 @@ HTMLInputElement::IsNodeApzAwareInternal() const
   return (mType == NS_FORM_INPUT_NUMBER) || (mType == NS_FORM_INPUT_RANGE) ||
          nsINode::IsNodeApzAwareInternal();
 }
+#endif
 
 bool
 HTMLInputElement::IsInteractiveHTMLContent(bool aIgnoreTabindex) const
@@ -4726,6 +4728,7 @@ HTMLInputElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
           }
           break;
         }
+#if !defined(XP_MACOSX)
         case eWheel: {
           // Handle wheel events as increasing / decreasing the input element's
           // value when it's focused and it's type is number or range.
@@ -4759,6 +4762,7 @@ HTMLInputElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
           }
           break;
         }
+#endif
         default:
           break;
       }
@@ -6651,9 +6655,11 @@ FireEventForAccessibility(nsIDOMHTMLInputElement* aTarget,
 void
 HTMLInputElement::UpdateApzAwareFlag()
 {
+#if !defined(XP_MACOSX)
   if ((mType == NS_FORM_INPUT_NUMBER) || (mType == NS_FORM_INPUT_RANGE)) {
     SetMayBeApzAware();
   }
+#endif
 }
 
 nsresult
@@ -7223,7 +7229,11 @@ HTMLInputElement::IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable, int32_t*
     return false;
   }
 
+#ifdef XP_MACOSX
+  const bool defaultFocusable = !aWithMouse || nsFocusManager::sMouseFocusesFormControl;
+#else
   const bool defaultFocusable = true;
+#endif
 
   if (mType == NS_FORM_INPUT_FILE ||
       mType == NS_FORM_INPUT_NUMBER ||
diff --git a/dom/html/HTMLInputElement.h b/dom/html/HTMLInputElement.h
index d7eccc0756..23c098df3b 100644
--- a/dom/html/HTMLInputElement.h
+++ b/dom/html/HTMLInputElement.h
@@ -137,7 +137,9 @@ public:
   virtual void Focus(ErrorResult& aError) override;
 
   // nsINode
+#if !defined(XP_MACOSX)
   virtual bool IsNodeApzAwareInternal() const override;
+#endif
 
   // Element
   virtual bool IsInteractiveHTMLContent(bool aIgnoreTabindex) const override;
diff --git a/dom/html/HTMLObjectElement.cpp b/dom/html/HTMLObjectElement.cpp
index a0d06a8c65..a77cd6fe57 100644
--- a/dom/html/HTMLObjectElement.cpp
+++ b/dom/html/HTMLObjectElement.cpp
@@ -18,6 +18,11 @@
 #include "nsNPAPIPluginInstance.h"
 #include "nsIWidget.h"
 #include "nsContentUtils.h"
+#ifdef XP_MACOSX
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/dom/Event.h"
+#include "nsFocusManager.h"
+#endif
 
 namespace mozilla {
 namespace dom {
@@ -39,6 +44,9 @@ HTMLObjectElement::HTMLObjectElement(already_AddRefed<mozilla::dom::NodeInfo>& a
 
 HTMLObjectElement::~HTMLObjectElement()
 {
+#ifdef XP_MACOSX
+  OnFocusBlurPlugin(this, false);
+#endif
   UnregisterActivityObserver();
   DestroyImageLoadingContent();
 }
@@ -109,6 +117,131 @@ NS_IMPL_ELEMENT_CLONE(HTMLObjectElement)
 // nsIConstraintValidation
 NS_IMPL_NSICONSTRAINTVALIDATION(HTMLObjectElement)
 
+#ifdef XP_MACOSX
+
+static nsIWidget* GetWidget(Element* aElement)
+{
+  return nsContentUtils::WidgetForDocument(aElement->OwnerDoc());
+}
+
+Element* HTMLObjectElement::sLastFocused = nullptr; // Weak
+
+class PluginFocusSetter : public Runnable
+{
+public:
+  PluginFocusSetter(nsIWidget* aWidget, Element* aElement)
+  : mWidget(aWidget), mElement(aElement)
+  {
+  }
+
+  NS_IMETHOD Run() override
+  {
+    if (mElement) {
+      HTMLObjectElement::sLastFocused = mElement;
+      bool value = true;
+      mWidget->SetPluginFocused(value);
+    } else if (!HTMLObjectElement::sLastFocused) {
+      bool value = false;
+      mWidget->SetPluginFocused(value);
+    }
+
+    return NS_OK;
+  }
+
+private:
+  nsCOMPtr<nsIWidget> mWidget;
+  nsCOMPtr<Element> mElement;
+};
+
+void
+HTMLObjectElement::OnFocusBlurPlugin(Element* aElement, bool aFocus)
+{
+  // In general we don't want to call nsIWidget::SetPluginFocused() for any
+  // Element that doesn't have a plugin running.  But if SetPluginFocused(true)
+  // was just called for aElement while it had a plugin running, we want to
+  // make sure nsIWidget::SetPluginFocused(false) gets called for it now, even
+  // if aFocus is true.
+  if (aFocus) {
+    nsCOMPtr<nsIObjectLoadingContent> olc = do_QueryInterface(aElement);
+    bool hasRunningPlugin = false;
+    if (olc) {
+      // nsIObjectLoadingContent::GetHasRunningPlugin() fails when
+      // nsContentUtils::IsCallerChrome() returns false (which it can do even
+      // when we're processing a trusted focus event).  We work around this by
+      // calling nsObjectLoadingContent::HasRunningPlugin() directly.
+      hasRunningPlugin =
+        static_cast<nsObjectLoadingContent*>(olc.get())->HasRunningPlugin();
+    }
+    if (!hasRunningPlugin) {
+      aFocus = false;
+    }
+  }
+
+  if (aFocus || aElement == sLastFocused) {
+    if (!aFocus) {
+      sLastFocused = nullptr;
+    }
+    nsIWidget* widget = GetWidget(aElement);
+    if (widget) {
+      nsContentUtils::AddScriptRunner(
+        new PluginFocusSetter(widget, aFocus ? aElement : nullptr));
+    }
+  }
+}
+
+void
+HTMLObjectElement::HandlePluginCrashed(Element* aElement)
+{
+  OnFocusBlurPlugin(aElement, false);
+}
+
+void
+HTMLObjectElement::HandlePluginInstantiated(Element* aElement)
+{
+  // If aElement is already focused when a plugin is instantiated, we need
+  // to initiate a call to nsIWidget::SetPluginFocused(true).  Otherwise
+  // keyboard input won't work in a click-to-play plugin until aElement
+  // loses focus and regains it.
+  nsIContent* focusedContent = nullptr;
+  nsFocusManager *fm = nsFocusManager::GetFocusManager();
+  if (fm) {
+    focusedContent = fm->GetFocusedContent();
+  }
+  if (SameCOMIdentity(focusedContent, aElement)) {
+    OnFocusBlurPlugin(aElement, true);
+  }
+}
+
+void
+HTMLObjectElement::HandleFocusBlurPlugin(Element* aElement,
+                                         WidgetEvent* aEvent)
+{
+  if (!aEvent->IsTrusted()) {
+    return;
+  }
+  switch (aEvent->mMessage) {
+    case eFocus: {
+      OnFocusBlurPlugin(aElement, true);
+      break;
+    }
+    case eBlur: {
+      OnFocusBlurPlugin(aElement, false);
+      break;
+    }
+    default:
+      break;
+  }
+}
+
+NS_IMETHODIMP
+HTMLObjectElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
+{
+  HandleFocusBlurPlugin(this, aVisitor.mEvent);
+  return NS_OK;
+}
+
+#endif // #ifdef XP_MACOSX
+
 NS_IMETHODIMP
 HTMLObjectElement::GetForm(nsIDOMHTMLFormElement **aForm)
 {
@@ -149,6 +282,14 @@ void
 HTMLObjectElement::UnbindFromTree(bool aDeep,
                                   bool aNullParent)
 {
+#ifdef XP_MACOSX
+  // When a page is reloaded (when an nsIDocument's content is removed), the
+  // focused element isn't necessarily sent an eBlur event. See
+  // nsFocusManager::ContentRemoved(). This means that a widget may think it
+  // still contains a focused plugin when it doesn't -- which in turn can
+  // disable text input in the browser window. See bug 1137229.
+  OnFocusBlurPlugin(this, false);
+#endif
   nsObjectLoadingContent::UnbindFromTree(aDeep, aNullParent);
   nsGenericHTMLFormElement::UnbindFromTree(aDeep, aNullParent);
 }
diff --git a/dom/html/HTMLSharedObjectElement.cpp b/dom/html/HTMLSharedObjectElement.cpp
index d7eec215a0..2aeb51573a 100644
--- a/dom/html/HTMLSharedObjectElement.cpp
+++ b/dom/html/HTMLSharedObjectElement.cpp
@@ -16,6 +16,10 @@
 #include "nsIScriptError.h"
 #include "nsIWidget.h"
 #include "nsContentUtils.h"
+#ifdef XP_MACOSX
+#include "mozilla/EventDispatcher.h"
+#include "mozilla/dom/Event.h"
+#endif
 #include "mozilla/dom/HTMLObjectElement.h"
 
 
@@ -38,6 +42,9 @@ HTMLSharedObjectElement::HTMLSharedObjectElement(already_AddRefed<mozilla::dom::
 
 HTMLSharedObjectElement::~HTMLSharedObjectElement()
 {
+#ifdef XP_MACOSX
+  HTMLObjectElement::OnFocusBlurPlugin(this, false);
+#endif
   UnregisterActivityObserver();
   DestroyImageLoadingContent();
 }
@@ -89,6 +96,17 @@ NS_INTERFACE_MAP_END_INHERITING(nsGenericHTMLElement)
 
 NS_IMPL_ELEMENT_CLONE(HTMLSharedObjectElement)
 
+#ifdef XP_MACOSX
+
+NS_IMETHODIMP
+HTMLSharedObjectElement::PostHandleEvent(EventChainPostVisitor& aVisitor)
+{
+  HTMLObjectElement::HandleFocusBlurPlugin(this, aVisitor.mEvent);
+  return NS_OK;
+}
+
+#endif // #ifdef XP_MACOSX
+
 void
 HTMLSharedObjectElement::AsyncEventRunning(AsyncEventDispatcher* aEvent)
 {
@@ -130,6 +148,14 @@ void
 HTMLSharedObjectElement::UnbindFromTree(bool aDeep,
                                         bool aNullParent)
 {
+#ifdef XP_MACOSX
+  // When a page is reloaded (when an nsIDocument's content is removed), the
+  // focused element isn't necessarily sent an eBlur event. See
+  // nsFocusManager::ContentRemoved(). This means that a widget may think it
+  // still contains a focused plugin when it doesn't -- which in turn can
+  // disable text input in the browser window. See bug 1137229.
+  HTMLObjectElement::OnFocusBlurPlugin(this, false);
+#endif
   nsObjectLoadingContent::UnbindFromTree(aDeep, aNullParent);
   nsGenericHTMLElement::UnbindFromTree(aDeep, aNullParent);
 }
diff --git a/dom/html/HTMLSharedObjectElement.h b/dom/html/HTMLSharedObjectElement.h
index 09b44fa115..e550b9927c 100644
--- a/dom/html/HTMLSharedObjectElement.h
+++ b/dom/html/HTMLSharedObjectElement.h
@@ -31,6 +31,11 @@ public:
 
   virtual int32_t TabIndexDefault() override;
 
+#ifdef XP_MACOSX
+  // nsIDOMEventTarget
+  NS_IMETHOD PostHandleEvent(EventChainPostVisitor& aVisitor) override;
+#endif
+
   // nsIDOMHTMLAppletElement
   NS_DECL_NSIDOMHTMLAPPLETELEMENT
 
diff --git a/dom/html/HTMLSummaryElement.cpp b/dom/html/HTMLSummaryElement.cpp
index b9de03fd11..ee3c07b20b 100644
--- a/dom/html/HTMLSummaryElement.cpp
+++ b/dom/html/HTMLSummaryElement.cpp
@@ -116,8 +116,15 @@ HTMLSummaryElement::IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
     return disallowOverridingFocusability;
   }
 
-  // The main summary element is focusable on all supported platforms.
+#ifdef XP_MACOSX
+  // The parent does not have strong opinion about the focusability of this main
+  // summary element, but we'd like to override it when mouse clicking on Mac OS
+  // like other form elements.
+  *aIsFocusable = !aWithMouse || nsFocusManager::sMouseFocusesFormControl;
+#else
+  // The main summary element is focusable on other platforms.
   *aIsFocusable = true;
+#endif
 
   // Give a chance to allow the subclass to override aIsFocusable.
   return false;
diff --git a/dom/html/nsGenericHTMLElement.cpp b/dom/html/nsGenericHTMLElement.cpp
index f7340ed7be..0f32d8fb42 100644
--- a/dom/html/nsGenericHTMLElement.cpp
+++ b/dom/html/nsGenericHTMLElement.cpp
@@ -2170,6 +2170,10 @@ nsGenericHTMLFormElement::IsHTMLFocusable(bool aWithMouse,
     return true;
   }
 
+#ifdef XP_MACOSX
+  *aIsFocusable =
+    (!aWithMouse || nsFocusManager::sMouseFocusesFormControl) && *aIsFocusable;
+#endif
   return false;
 }
 
diff --git a/dom/media/GraphDriver.cpp b/dom/media/GraphDriver.cpp
index daf1ccc989..c4ee2ee2b1 100644
--- a/dom/media/GraphDriver.cpp
+++ b/dom/media/GraphDriver.cpp
@@ -14,6 +14,10 @@
 #include "webrtc/MediaEngineWebRTC.h"
 #endif
 
+#ifdef XP_MACOSX
+#include <sys/sysctl.h>
+#endif
+
 extern mozilla::LazyLogModule gMediaStreamGraphLog;
 #define STREAM_LOG(type, msg) MOZ_LOG(gMediaStreamGraphLog, type, msg)
 
@@ -577,6 +581,32 @@ AudioCallbackDriver::~AudioCallbackDriver()
   MOZ_ASSERT(mPromisesForOperation.IsEmpty());
 }
 
+bool IsMacbookOrMacbookAir()
+{
+#ifdef XP_MACOSX
+  size_t len = 0;
+  sysctlbyname("hw.model", NULL, &len, NULL, 0);
+  if (len) {
+    UniquePtr<char[]> model(new char[len]);
+    // This string can be
+    // MacBook%d,%d for a normal MacBook
+    // MacBookPro%d,%d for a MacBook Pro
+    // MacBookAir%d,%d for a Macbook Air
+    sysctlbyname("hw.model", model.get(), &len, NULL, 0);
+    char* substring = strstr(model.get(), "MacBook");
+    if (substring) {
+      const size_t offset = strlen("MacBook");
+      if (strncmp(model.get() + offset, "Air", len - offset) ||
+          isdigit(model[offset + 1])) {
+        return true;
+      }
+    }
+    return false;
+  }
+#endif
+  return false;
+}
+
 void
 AudioCallbackDriver::Init()
 {
@@ -613,6 +643,13 @@ AudioCallbackDriver::Init()
     }
   }
 
+  // Macbook and MacBook air don't have enough CPU to run very low latency
+  // MediaStreamGraphs, cap the minimal latency to 512 frames int this case.
+  if (IsMacbookOrMacbookAir()) {
+    latency_frames = std::max((uint32_t) 512, latency_frames);
+  }
+
+
   input = output;
   input.channels = mInputChannels; // change to support optional stereo capture
 
@@ -1026,6 +1063,44 @@ AudioCallbackDriver::MixerCallback(AudioDataValue* aMixedBuffer,
   NS_WARNING_ASSERTION(written == aFrames - toWrite, "Dropping frames.");
 };
 
+void AudioCallbackDriver::PanOutputIfNeeded(bool aMicrophoneActive)
+{
+#ifdef XP_MACOSX
+  cubeb_device* out;
+  int rv;
+  char name[128];
+  size_t length = sizeof(name);
+
+  rv = sysctlbyname("hw.model", name, &length, NULL, 0);
+  if (rv) {
+    return;
+  }
+
+  if (!strncmp(name, "MacBookPro", 10)) {
+    if (cubeb_stream_get_current_device(mAudioStream, &out) == CUBEB_OK) {
+      // Check if we are currently outputing sound on external speakers.
+      if (!strcmp(out->output_name, "ispk")) {
+        // Pan everything to the right speaker.
+        if (aMicrophoneActive) {
+          if (cubeb_stream_set_panning(mAudioStream, 1.0) != CUBEB_OK) {
+            NS_WARNING("Could not pan audio output to the right.");
+          }
+        } else {
+          if (cubeb_stream_set_panning(mAudioStream, 0.0) != CUBEB_OK) {
+            NS_WARNING("Could not pan audio output to the center.");
+          }
+        }
+      } else {
+        if (cubeb_stream_set_panning(mAudioStream, 0.0) != CUBEB_OK) {
+          NS_WARNING("Could not pan audio output to the center.");
+        }
+      }
+      cubeb_stream_device_destroy(mAudioStream, out);
+    }
+  }
+#endif
+}
+
 void
 AudioCallbackDriver::DeviceChangedCallback() {
   // Tell the audio engine the device has changed, it might want to reset some
@@ -1034,6 +1109,9 @@ AudioCallbackDriver::DeviceChangedCallback() {
   if (mAudioInput) {
     mAudioInput->DeviceChanged();
   }
+#ifdef XP_MACOSX
+  PanOutputIfNeeded(mMicrophoneActive);
+#endif
 }
 
 void
@@ -1042,6 +1120,10 @@ AudioCallbackDriver::SetMicrophoneActive(bool aActive)
   MonitorAutoLock mon(mGraphImpl->GetMonitor());
 
   mMicrophoneActive = aActive;
+
+#ifdef XP_MACOSX
+  PanOutputIfNeeded(mMicrophoneActive);
+#endif
 }
 
 uint32_t
diff --git a/dom/media/GraphDriver.h b/dom/media/GraphDriver.h
index f2a514b328..bb4f2689b8 100644
--- a/dom/media/GraphDriver.h
+++ b/dom/media/GraphDriver.h
@@ -457,6 +457,11 @@ public:
   void CompleteAudioContextOperations(AsyncCubebOperation aOperation);
 private:
   /**
+   * On certain MacBookPro, the microphone is located near the left speaker.
+   * We need to pan the sound output to the right speaker if we are using the
+   * mic and the built-in speaker, or we will have terrible echo.  */
+  void PanOutputIfNeeded(bool aMicrophoneActive);
+  /**
    * This is called when the output device used by the cubeb stream changes. */
   void DeviceChangedCallback();
   /* Start the cubeb stream */
diff --git a/dom/media/eme/MediaKeySystemAccessManager.cpp b/dom/media/eme/MediaKeySystemAccessManager.cpp
index a1e1254ad4..ed31059e22 100644
--- a/dom/media/eme/MediaKeySystemAccessManager.cpp
+++ b/dom/media/eme/MediaKeySystemAccessManager.cpp
@@ -14,6 +14,9 @@
 #ifdef XP_WIN
 #include "mozilla/WindowsVersion.h"
 #endif
+#ifdef XP_MACOSX
+#include "nsCocoaFeatures.h"
+#endif
 #include "nsPrintfCString.h"
 
 namespace mozilla {
diff --git a/dom/media/gmp/GMPChild.cpp b/dom/media/gmp/GMPChild.cpp
index eb18037364..fa6f2f4c83 100644
--- a/dom/media/gmp/GMPChild.cpp
+++ b/dom/media/gmp/GMPChild.cpp
@@ -112,12 +112,14 @@ GetPluginFile(const nsAString& aPluginPath,
   nsAutoString baseName;
   GetFileBase(aPluginPath, aLibDirectory, aLibFile, baseName);
 
-#if defined(OS_POSIX)
+#if defined(XP_MACOSX)
+  nsAutoString binaryName = NS_LITERAL_STRING("lib") + baseName + NS_LITERAL_STRING(".dylib");
+#elif defined(OS_POSIX)
   nsAutoString binaryName = NS_LITERAL_STRING("lib") + baseName + NS_LITERAL_STRING(".so");
 #elif defined(XP_WIN)
   nsAutoString binaryName =                            baseName + NS_LITERAL_STRING(".dll");
 #else
-#error Unsupported O.S.
+#error not defined
 #endif
   aLibFile->AppendRelativePath(binaryName);
   return true;
diff --git a/dom/media/gmp/rlz/GMPDeviceBinding.cpp b/dom/media/gmp/rlz/GMPDeviceBinding.cpp
index 0871d2e4ee..04def8e8e0 100644
--- a/dom/media/gmp/rlz/GMPDeviceBinding.cpp
+++ b/dom/media/gmp/rlz/GMPDeviceBinding.cpp
@@ -32,6 +32,14 @@
 #include "windows.h"
 #endif
 
+#ifdef XP_MACOSX
+#include <assert.h>
+#ifdef HASH_NODE_ID_WITH_DEVICE_ID
+#include <unistd.h>
+#include <mach/mach.h>
+#include <mach/mach_vm.h>
+#endif
+#endif
 
 #endif // HASH_NODE_ID_WITH_DEVICE_ID
 
@@ -75,6 +83,46 @@ GetStackAfterCurrentFrame(uint8_t** aOutTop, uint8_t** aOutBottom)
 }
 #endif
 
+#if defined(XP_MACOSX) && defined(HASH_NODE_ID_WITH_DEVICE_ID)
+static mach_vm_address_t
+RegionContainingAddress(mach_vm_address_t aAddress)
+{
+  mach_port_t task;
+  kern_return_t kr = task_for_pid(mach_task_self(), getpid(), &task);
+  if (kr != KERN_SUCCESS) {
+    return 0;
+  }
+
+  mach_vm_address_t address = aAddress;
+  mach_vm_size_t size;
+  vm_region_basic_info_data_64_t info;
+  mach_msg_type_number_t count = VM_REGION_BASIC_INFO_COUNT_64;
+  mach_port_t object_name;
+  kr = mach_vm_region(task, &address, &size, VM_REGION_BASIC_INFO_64,
+                      reinterpret_cast<vm_region_info_t>(&info), &count,
+                      &object_name);
+  if (kr != KERN_SUCCESS || size == 0
+      || address > aAddress || address + size <= aAddress) {
+    // mach_vm_region failed, or couldn't find region at given address.
+    return 0;
+  }
+
+  return address;
+}
+
+MOZ_NEVER_INLINE
+static bool
+GetStackAfterCurrentFrame(uint8_t** aOutTop, uint8_t** aOutBottom)
+{
+  mach_vm_address_t stackFrame =
+    reinterpret_cast<mach_vm_address_t>(__builtin_frame_address(0));
+  *aOutTop = reinterpret_cast<uint8_t*>(stackFrame);
+  // Kernel code shows that stack is always a single region.
+  *aOutBottom = reinterpret_cast<uint8_t*>(RegionContainingAddress(stackFrame));
+  return *aOutBottom && (*aOutBottom < *aOutTop);
+}
+#endif
+
 #ifdef HASH_NODE_ID_WITH_DEVICE_ID
 static void SecureMemset(void* start, uint8_t value, size_t size)
 {
diff --git a/dom/media/systemservices/LoadMonitor.cpp b/dom/media/systemservices/LoadMonitor.cpp
index 9ef01999c0..c05d43b1e5 100644
--- a/dom/media/systemservices/LoadMonitor.cpp
+++ b/dom/media/systemservices/LoadMonitor.cpp
@@ -31,6 +31,12 @@
 #include <unistd.h>
 #endif
 
+#ifdef XP_MACOSX
+#include <mach/mach_host.h>
+#include <mach/mach_init.h>
+#include <mach/host_info.h>
+#endif
+
 #if defined(__DragonFly__) || defined(__FreeBSD__) \
  || defined(__NetBSD__) || defined(__OpenBSD__)
 #include <sys/sysctl.h>
@@ -407,6 +413,27 @@ nsresult RTCLoadInfo::UpdateSystemLoad()
                 cpu_times,
                 &mSystemLoad);
   return NS_OK;
+#elif defined(XP_MACOSX)
+  mach_msg_type_number_t info_cnt = HOST_CPU_LOAD_INFO_COUNT;
+  host_cpu_load_info_data_t load_info;
+  kern_return_t rv = host_statistics(mach_host_self(), HOST_CPU_LOAD_INFO,
+                                     (host_info_t)(&load_info), &info_cnt);
+
+  if (rv != KERN_SUCCESS || info_cnt != HOST_CPU_LOAD_INFO_COUNT) {
+    LOG(("Error from mach/host_statistics call"));
+    return NS_ERROR_FAILURE;
+  }
+
+  const uint64_t cpu_times = load_info.cpu_ticks[CPU_STATE_NICE]
+                           + load_info.cpu_ticks[CPU_STATE_SYSTEM]
+                           + load_info.cpu_ticks[CPU_STATE_USER];
+  const uint64_t total_times = cpu_times + load_info.cpu_ticks[CPU_STATE_IDLE];
+
+  UpdateCpuLoad(mTicksPerInterval,
+                total_times,
+                cpu_times,
+                &mSystemLoad);
+  return NS_OK;
 #elif defined(__DragonFly__) || defined(__FreeBSD__) \
    || defined(__NetBSD__) || defined(__OpenBSD__)
 #if defined(__NetBSD__)
diff --git a/dom/media/webaudio/AudioContext.cpp b/dom/media/webaudio/AudioContext.cpp
index 3c7958349b..75f57a630b 100755
--- a/dom/media/webaudio/AudioContext.cpp
+++ b/dom/media/webaudio/AudioContext.cpp
@@ -873,6 +873,7 @@ AudioContext::OnStateChanged(void* aPromise, AudioContextState aNewState)
   }
 
 #ifndef WIN32 // Bug 1170547
+#ifndef XP_MACOSX
 #ifdef DEBUG
 
   if (!((mAudioContextState == AudioContextState::Suspended &&
@@ -891,6 +892,7 @@ AudioContext::OnStateChanged(void* aPromise, AudioContextState aNewState)
   }
 
 #endif // DEBUG
+#endif // XP_MACOSX
 #endif // WIN32
 
   MOZ_ASSERT(
diff --git a/dom/media/webrtc/MediaEngineCameraVideoSource.cpp b/dom/media/webrtc/MediaEngineCameraVideoSource.cpp
index e63a9afded..e1e572724f 100644
--- a/dom/media/webrtc/MediaEngineCameraVideoSource.cpp
+++ b/dom/media/webrtc/MediaEngineCameraVideoSource.cpp
@@ -339,6 +339,13 @@ MediaEngineCameraVideoSource::SetName(nsString aName)
     facingMode = VideoFacingModeEnum::User;
   }
 #endif // ANDROID
+#ifdef XP_MACOSX
+  // Kludge to test user-facing cameras on OSX.
+  if (aName.Find(NS_LITERAL_STRING("Face")) != -1) {
+    hasFacingMode = true;
+    facingMode = VideoFacingModeEnum::User;
+  }
+#endif
 #ifdef XP_WIN
   // The cameras' name of Surface book are "Microsoft Camera Front" and
   // "Microsoft Camera Rear" respectively.
diff --git a/dom/plugins/base/PluginPRLibrary.cpp b/dom/plugins/base/PluginPRLibrary.cpp
index e6a202c244..57c6c57ab3 100644
--- a/dom/plugins/base/PluginPRLibrary.cpp
+++ b/dom/plugins/base/PluginPRLibrary.cpp
@@ -24,7 +24,7 @@ static int gNotOptimized;
 using namespace mozilla::layers;
 
 namespace mozilla {
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
 nsresult
 PluginPRLibrary::NP_Initialize(NPNetscapeFuncs* bFuncs,
                                NPPluginFuncs* pFuncs, NPError* error)
@@ -110,7 +110,7 @@ nsresult
 PluginPRLibrary::NP_GetValue(void *future, NPPVariable aVariable,
 			     void *aValue, NPError* error)
 {
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
   if (mNP_GetValue) {
     *error = mNP_GetValue(future, aVariable, aValue);
   } else {
@@ -125,7 +125,7 @@ PluginPRLibrary::NP_GetValue(void *future, NPPVariable aVariable,
 #endif
 }
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
 nsresult
 PluginPRLibrary::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error)
 {
@@ -231,7 +231,17 @@ PluginPRLibrary::GetImageContainer(NPP instance, ImageContainer** aContainer)
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+nsresult
+PluginPRLibrary::IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing)
+{
+  nsNPAPIPluginInstance* inst = (nsNPAPIPluginInstance*)instance->ndata;
+  NS_ENSURE_TRUE(inst, NS_ERROR_NULL_POINTER);
+  *aDrawing = false; 
+  return NS_OK;
+}
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
 nsresult
 PluginPRLibrary::ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor)
 {
diff --git a/dom/plugins/base/PluginPRLibrary.h b/dom/plugins/base/PluginPRLibrary.h
index 4934b37bbb..ffd3de934e 100644
--- a/dom/plugins/base/PluginPRLibrary.h
+++ b/dom/plugins/base/PluginPRLibrary.h
@@ -17,17 +17,17 @@ class PluginPRLibrary : public PluginLibrary
 {
 public:
     PluginPRLibrary(const char* aFilePath, PRLibrary* aLibrary) :
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
         mNP_Initialize(nullptr),
 #else
         mNP_Initialize(nullptr),
 #endif
         mNP_Shutdown(nullptr),
         mNP_GetMIMEDescription(nullptr),
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
         mNP_GetValue(nullptr),
 #endif
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
         mNP_GetEntryPoints(nullptr),
 #endif
         mNPP_New(nullptr),
@@ -60,17 +60,19 @@ public:
 
         mNP_GetMIMEDescription = (NP_GetMIMEDescriptionFunc)
             PR_FindFunctionSymbol(mLibrary, "NP_GetMIMEDescription");
+#ifndef XP_MACOSX
         if (!mNP_GetMIMEDescription)
             return false;
+#endif
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
         mNP_GetValue = (NP_GetValueFunc)
             PR_FindFunctionSymbol(mLibrary, "NP_GetValue");
         if (!mNP_GetValue)
             return false;
 #endif
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
         mNP_GetEntryPoints = (NP_GetEntryPointsFunc)
             PR_FindFunctionSymbol(mLibrary, "NP_GetEntryPoints");
         if (!mNP_GetEntryPoints)
@@ -79,7 +81,7 @@ public:
         return true;
     }
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
     virtual nsresult NP_Initialize(NPNetscapeFuncs* aNetscapeFuncs,
                                    NPPluginFuncs* aFuncs, NPError* aError) override;
 #else
@@ -93,7 +95,7 @@ public:
     virtual nsresult NP_GetValue(void* aFuture, NPPVariable aVariable,
                                  void* aValue, NPError* aError) override;
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
     virtual nsresult NP_GetEntryPoints(NPPluginFuncs* aFuncs, NPError* aError) override;
 #endif
 
@@ -110,7 +112,10 @@ public:
     virtual nsresult GetImageContainer(NPP aInstance, mozilla::layers::ImageContainer** aContainer) override;
     virtual nsresult GetImageSize(NPP aInstance, nsIntSize* aSize) override;
     virtual bool IsOOP() override { return false; }
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+    virtual nsresult IsRemoteDrawingCoreAnimation(NPP aInstance, bool* aDrawing) override;
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
     virtual nsresult ContentsScaleFactorChanged(NPP aInstance, double aContentsScaleFactor) override;
 #endif
     virtual nsresult SetBackgroundUnknown(NPP instance) override;
@@ -134,10 +139,10 @@ private:
     NP_InitializeFunc mNP_Initialize;
     NP_ShutdownFunc mNP_Shutdown;
     NP_GetMIMEDescriptionFunc mNP_GetMIMEDescription;
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
     NP_GetValueFunc mNP_GetValue;
 #endif
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
     NP_GetEntryPointsFunc mNP_GetEntryPoints;
 #endif
     NPP_NewProcPtr mNPP_New;
diff --git a/dom/plugins/base/npapi.h b/dom/plugins/base/npapi.h
index de58f818c4..aa6a66b2bd 100644
--- a/dom/plugins/base/npapi.h
+++ b/dom/plugins/base/npapi.h
@@ -22,6 +22,25 @@
 #endif
 #endif
 
+#if defined(__APPLE_CC__) && !defined(XP_UNIX)
+#ifndef XP_MACOSX
+#define XP_MACOSX 1
+#endif
+#endif
+
+#if defined(XP_MACOSX) && defined(__LP64__)
+#define NP_NO_QUICKDRAW
+#define NP_NO_CARBON
+#endif
+
+#if defined(XP_MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#include <OpenGL/OpenGL.h>
+#ifndef NP_NO_CARBON
+#include <Carbon/Carbon.h>
+#endif
+#endif
+
 #if defined(XP_UNIX)
 #include <stdio.h>
 #if defined(MOZ_X11)
@@ -98,6 +117,12 @@ typedef char*         NPMIMEType;
 /*                       Structures and definitions                     */
 /*----------------------------------------------------------------------*/
 
+#if !defined(__LP64__)
+#if defined(XP_MACOSX)
+#pragma options align=mac68k
+#endif
+#endif /* __LP64__ */
+
 /*
  *  NPP is a plug-in's opaque instance handle
  */
@@ -255,6 +280,15 @@ typedef struct _NPAudioDeviceChangeDetails
 
 typedef enum {
   NPDrawingModelDUMMY
+#if defined(XP_MACOSX)
+#ifndef NP_NO_QUICKDRAW
+  , NPDrawingModelQuickDraw = 0
+#endif
+  , NPDrawingModelCoreGraphics = 1
+  , NPDrawingModelOpenGL = 2
+  , NPDrawingModelCoreAnimation = 3
+  , NPDrawingModelInvalidatingCoreAnimation = 4
+#endif
 #if defined(XP_WIN)
   , NPDrawingModelSyncWin = 5
 #endif
@@ -267,6 +301,15 @@ typedef enum {
 #endif
 } NPDrawingModel;
 
+#ifdef XP_MACOSX
+typedef enum {
+#ifndef NP_NO_CARBON
+  NPEventModelCarbon = 0,
+#endif
+  NPEventModelCocoa = 1
+} NPEventModel;
+#endif
+
 /*
  *   The following masks are applied on certain platforms to NPNV and
  *   NPPV selectors that pass around pointers to COM interfaces. Newer
@@ -294,7 +337,12 @@ typedef enum {
 #define _NP_ABI_MIXIN_FOR_GCC3 0
 #endif
 
+#if defined(XP_MACOSX)
+#define NP_ABI_MACHO_MASK 0x01000000
+#define _NP_ABI_MIXIN_FOR_MACHO NP_ABI_MACHO_MASK
+#else
 #define _NP_ABI_MIXIN_FOR_MACHO 0
+#endif
 
 #define NP_ABI_MASK (_NP_ABI_MIXIN_FOR_GCC3 | _NP_ABI_MIXIN_FOR_MACHO)
 
@@ -345,6 +393,12 @@ typedef enum {
 
   /* Used for negotiating drawing models */
   NPPVpluginDrawingModel = 1000
+#if defined(XP_MACOSX)
+  /* Used for negotiating event models */
+  , NPPVpluginEventModel = 1001
+  /* In the NPDrawingModelCoreAnimation drawing model, the browser asks the plug-in for a Core Animation layer. */
+  , NPPVpluginCoreAnimationLayer = 1003
+#endif
   /* Notification that the plugin just started or stopped playing audio */
   , NPPVpluginIsPlayingAudio = 4000
 #if defined(XP_WIN)
@@ -388,18 +442,39 @@ typedef enum {
   NPNVCSSZoomFactor = 23,
 
   NPNVpluginDrawingModel = 1000 /* Get the current drawing model (NPDrawingModel) */
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   , NPNVcontentsScaleFactor = 1001
 #endif
+#if defined(XP_MACOSX)
+#ifndef NP_NO_QUICKDRAW
+  , NPNVsupportsQuickDrawBool = 2000
+#endif
+  , NPNVsupportsCoreGraphicsBool = 2001
+  , NPNVsupportsOpenGLBool = 2002
+  , NPNVsupportsCoreAnimationBool = 2003
+  , NPNVsupportsInvalidatingCoreAnimationBool = 2004
+#endif
   , NPNVsupportsAsyncBitmapSurfaceBool = 2007
 #if defined(XP_WIN)
   , NPNVsupportsAsyncWindowsDXGISurfaceBool = 2008
   , NPNVpreferredDXGIAdapter = 2009
 #endif
+#if defined(XP_MACOSX)
+#ifndef NP_NO_CARBON
+  , NPNVsupportsCarbonBool = 3000 /* TRUE if the browser supports the Carbon event model */
+#endif
+  , NPNVsupportsCocoaBool = 3001 /* TRUE if the browser supports the Cocoa event model */
+  , NPNVsupportsUpdatedCocoaTextInputBool = 3002 /* TRUE if the browser supports the updated
+                                                    Cocoa text input specification. */
+#endif
   , NPNVmuteAudioBool = 4000 /* Request that the browser wants to mute or unmute the plugin */
 #if defined(XP_WIN)
   , NPNVaudioDeviceChangeDetails = 4001 /* Provides information about the new default audio device */
 #endif
+#if defined(XP_MACOSX)
+  , NPNVsupportsCompositingCoreAnimationPluginsBool = 74656 /* TRUE if the browser supports
+                                                               CA model compositing */
+#endif
 } NPNVariable;
 
 typedef enum {
@@ -434,7 +509,7 @@ typedef struct _NPWindow
   uint32_t width;  /* Maximum window size */
   uint32_t height;
   NPRect   clipRect; /* Clipping rectangle in port coordinates */
-#if defined(XP_UNIX) || defined(XP_SYMBIAN)
+#if (defined(XP_UNIX) || defined(XP_SYMBIAN)) && !defined(XP_MACOSX)
   void * ws_info; /* Platform-dependent additional data */
 #endif /* XP_UNIX */
   NPWindowType type; /* Is this a window or a drawable? */
@@ -480,7 +555,11 @@ typedef struct _NPPrint
   } print;
 } NPPrint;
 
-#if defined(XP_SYMBIAN)
+#if defined(XP_MACOSX)
+#ifndef NP_NO_CARBON
+typedef EventRecord NPEvent;
+#endif
+#elif defined(XP_SYMBIAN)
 typedef QEvent NPEvent;
 #elif defined(XP_WIN)
 typedef struct _NPEvent
@@ -495,7 +574,13 @@ typedef XEvent NPEvent;
 typedef void*  NPEvent;
 #endif
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+typedef void* NPRegion;
+#ifndef NP_NO_QUICKDRAW
+typedef RgnHandle NPQDRegion;
+#endif
+typedef CGPathRef NPCGRegion;
+#elif defined(XP_WIN)
 typedef HRGN NPRegion;
 #elif defined(XP_UNIX) && defined(MOZ_X11)
 typedef Region NPRegion;
@@ -509,7 +594,11 @@ typedef struct _NPNSString NPNSString;
 typedef struct _NPNSWindow NPNSWindow;
 typedef struct _NPNSMenu   NPNSMenu;
 
+#if defined(XP_MACOSX)
+typedef NPNSMenu NPMenu;
+#else
 typedef void *NPMenu;
+#endif
 
 typedef enum {
   NPCoordinateSpacePlugin = 1,
@@ -519,6 +608,112 @@ typedef enum {
   NPCoordinateSpaceFlippedScreen
 } NPCoordinateSpace;
 
+#if defined(XP_MACOSX)
+
+#ifndef NP_NO_QUICKDRAW
+typedef struct NP_Port
+{
+  CGrafPtr port;
+  int32_t portx; /* position inside the topmost window */
+  int32_t porty;
+} NP_Port;
+#endif /* NP_NO_QUICKDRAW */
+
+/*
+ * NP_CGContext is the type of the NPWindow's 'window' when the plugin specifies NPDrawingModelCoreGraphics
+ * as its drawing model.
+ */
+
+typedef struct NP_CGContext
+{
+  CGContextRef context;
+  void *window; /* A WindowRef under the Carbon event model. */
+} NP_CGContext;
+
+/*
+ * NP_GLContext is the type of the NPWindow's 'window' when the plugin specifies NPDrawingModelOpenGL as its
+ * drawing model.
+ */
+
+typedef struct NP_GLContext
+{
+  CGLContextObj context;
+#ifdef NP_NO_CARBON
+  NPNSWindow *window;
+#else
+  void *window; /* Can be either an NSWindow or a WindowRef depending on the event model */
+#endif
+} NP_GLContext;
+
+typedef enum {
+  NPCocoaEventDrawRect = 1,
+  NPCocoaEventMouseDown,
+  NPCocoaEventMouseUp,
+  NPCocoaEventMouseMoved,
+  NPCocoaEventMouseEntered,
+  NPCocoaEventMouseExited,
+  NPCocoaEventMouseDragged,
+  NPCocoaEventKeyDown,
+  NPCocoaEventKeyUp,
+  NPCocoaEventFlagsChanged,
+  NPCocoaEventFocusChanged,
+  NPCocoaEventWindowFocusChanged,
+  NPCocoaEventScrollWheel,
+  NPCocoaEventTextInput
+} NPCocoaEventType;
+
+typedef struct _NPCocoaEvent {
+  NPCocoaEventType type;
+  uint32_t version;
+  union {
+    struct {
+      uint32_t modifierFlags;
+      double   pluginX;
+      double   pluginY;
+      int32_t  buttonNumber;
+      int32_t  clickCount;
+      double   deltaX;
+      double   deltaY;
+      double   deltaZ;
+    } mouse;
+    struct {
+      uint32_t    modifierFlags;
+      NPNSString *characters;
+      NPNSString *charactersIgnoringModifiers;
+      NPBool      isARepeat;
+      uint16_t    keyCode;
+    } key;
+    struct {
+      CGContextRef context;
+      double x;
+      double y;
+      double width;
+      double height;
+    } draw;
+    struct {
+      NPBool hasFocus;
+    } focus;
+    struct {
+      NPNSString *text;
+    } text;
+  } data;
+} NPCocoaEvent;
+
+#ifndef NP_NO_CARBON
+/* Non-standard event types that can be passed to HandleEvent */
+enum NPEventType {
+  NPEventType_GetFocusEvent = (osEvt + 16),
+  NPEventType_LoseFocusEvent,
+  NPEventType_AdjustCursorEvent,
+  NPEventType_MenuCommandEvent,
+  NPEventType_ClippingChangedEvent,
+  NPEventType_ScrollingBeginsEvent = 1000,
+  NPEventType_ScrollingEndsEvent
+};
+#endif /* NP_NO_CARBON */
+
+#endif /* XP_MACOSX */
+
 /*
  * Values for mode passed to NPP_New:
  */
@@ -541,6 +736,12 @@ typedef enum {
 #define NP_CLEAR_ALL   0
 #define NP_CLEAR_CACHE (1 << 0)
 
+#if !defined(__LP64__)
+#if defined(XP_MACOSX)
+#pragma options align=reset
+#endif
+#endif /* __LP64__ */
+
 /*----------------------------------------------------------------------*/
 /*       Error and Reason Code definitions                              */
 /*----------------------------------------------------------------------*/
diff --git a/dom/plugins/base/npfunctions.h b/dom/plugins/base/npfunctions.h
index 83c8a9762c..dca542b620 100644
--- a/dom/plugins/base/npfunctions.h
+++ b/dom/plugins/base/npfunctions.h
@@ -182,6 +182,31 @@ typedef struct _NPNetscapeFuncs {
   NPN_SetCurrentAsyncSurfacePtr setcurrentasyncsurface;
 } NPNetscapeFuncs;
 
+#ifdef XP_MACOSX
+/*
+ * Mac OS X version(s) of NP_GetMIMEDescription(const char *)
+ * These can be called to retreive MIME information from the plugin dynamically
+ *
+ * Note: For compatibility with Quicktime, BPSupportedMIMEtypes is another way
+ *       to get mime info from the plugin only on OSX and may not be supported
+ *       in furture version -- use NP_GetMIMEDescription instead
+ */
+enum
+{
+ kBPSupportedMIMETypesStructVers_1    = 1
+};
+typedef struct _BPSupportedMIMETypes
+{
+ SInt32    structVersion;      /* struct version */
+ Handle    typeStrings;        /* STR# formated handle, allocated by plug-in */
+ Handle    infoStrings;        /* STR# formated handle, allocated by plug-in */
+} BPSupportedMIMETypes;
+OSErr BP_GetSupportedMIMETypes(BPSupportedMIMETypes *mimeInfo, UInt32 flags);
+#define NP_GETMIMEDESCRIPTION_NAME "NP_GetMIMEDescription"
+typedef const char* (*NP_GetMIMEDescriptionProcPtr)(void);
+typedef OSErr (*BP_GetSupportedMIMETypesProcPtr)(BPSupportedMIMETypes*, UInt32);
+#endif
+
 #if defined(_WIN32)
 #define OSCALL WINAPI
 #else
@@ -226,8 +251,15 @@ typedef char*          (*NP_GetPluginVersionFunc)(void);
 NP_EXPORT(char*)       NP_GetPluginVersion(void);
 typedef const char*    (*NP_GetMIMEDescriptionFunc)(void);
 NP_EXPORT(const char*) NP_GetMIMEDescription(void);
+#ifdef XP_MACOSX
+typedef NPError        (*NP_InitializeFunc)(NPNetscapeFuncs*);
+NP_EXPORT(NPError)     NP_Initialize(NPNetscapeFuncs* bFuncs);
+typedef NPError        (*NP_GetEntryPointsFunc)(NPPluginFuncs*);
+NP_EXPORT(NPError)     NP_GetEntryPoints(NPPluginFuncs* pFuncs);
+#else
 typedef NPError    (*NP_InitializeFunc)(NPNetscapeFuncs*, NPPluginFuncs*);
 NP_EXPORT(NPError) NP_Initialize(NPNetscapeFuncs* bFuncs, NPPluginFuncs* pFuncs);
+#endif
 typedef NPError        (*NP_ShutdownFunc)(void);
 NP_EXPORT(NPError)     NP_Shutdown(void);
 typedef NPError        (*NP_GetValueFunc)(void *, NPPVariable, void *);
diff --git a/dom/plugins/base/nsNPAPIPlugin.cpp b/dom/plugins/base/nsNPAPIPlugin.cpp
index b2e931483f..da4f09914f 100644
--- a/dom/plugins/base/nsNPAPIPlugin.cpp
+++ b/dom/plugins/base/nsNPAPIPlugin.cpp
@@ -269,6 +269,14 @@ nsNPAPIPlugin::CreatePlugin(nsPluginTag *aPluginTag, nsNPAPIPlugin** aResult)
     return NS_ERROR_FAILURE;
   }
 
+#ifdef XP_MACOSX
+  if (!pluginLib->HasRequiredFunctions()) {
+    NS_WARNING("Not all necessary functions exposed by plugin, it will not load.");
+    delete pluginLib;
+    return NS_ERROR_FAILURE;
+  }
+#endif
+
   plugin->mLibrary = pluginLib;
   pluginLib->SetPlugin(plugin);
 
@@ -286,6 +294,19 @@ nsNPAPIPlugin::CreatePlugin(nsPluginTag *aPluginTag, nsNPAPIPlugin** aResult)
   if (rv != NS_OK || pluginCallError != NPERR_NO_ERROR) {
     return NS_ERROR_FAILURE;
   }
+#elif defined(XP_MACOSX)
+  // NP_Initialize must be called before NP_GetEntryPoints on Mac OS X.
+  // We need to match WebKit's behavior.
+  NPError pluginCallError;
+  nsresult rv = pluginLib->NP_Initialize(&sBrowserFuncs, &pluginCallError);
+  if (rv != NS_OK || pluginCallError != NPERR_NO_ERROR) {
+    return NS_ERROR_FAILURE;
+  }
+
+  rv = pluginLib->NP_GetEntryPoints(&plugin->mPluginFuncs, &pluginCallError);
+  if (rv != NS_OK || pluginCallError != NPERR_NO_ERROR) {
+    return NS_ERROR_FAILURE;
+  }
 #else
   NPError pluginCallError;
   nsresult rv = pluginLib->NP_Initialize(&sBrowserFuncs, &plugin->mPluginFuncs, &pluginCallError);
@@ -1708,7 +1729,7 @@ _getvalue(NPP npp, NPNVariable variable, void *result)
   // cases for android_npapi.h's non-standard ANPInterface values.
   switch (static_cast<int>(variable)) {
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
   case NPNVxDisplay : {
 #if defined(MOZ_X11)
     if (npp) {
@@ -1833,7 +1854,8 @@ _getvalue(NPP npp, NPNVariable variable, void *result)
   }
 
   case NPNVSupportsWindowless: {
-#if defined(XP_WIN) || (defined(MOZ_X11) && defined(MOZ_WIDGET_GTK))
+#if defined(XP_WIN) || defined(XP_MACOSX) || \
+    (defined(MOZ_X11) && defined(MOZ_WIDGET_GTK))
     *(NPBool*)result = true;
 #else
     *(NPBool*)result = false;
@@ -1901,7 +1923,72 @@ _getvalue(NPP npp, NPNVariable variable, void *result)
     return *(char**)result ? NPERR_NO_ERROR : NPERR_GENERIC_ERROR;
   }
 
-#if defined(XP_WIN)
+#ifdef XP_MACOSX
+  case NPNVpluginDrawingModel: {
+    if (npp) {
+      nsNPAPIPluginInstance *inst = (nsNPAPIPluginInstance*)npp->ndata;
+      if (inst) {
+        NPDrawingModel drawingModel;
+        inst->GetDrawingModel((int32_t*)&drawingModel);
+        *(NPDrawingModel*)result = drawingModel;
+        return NPERR_NO_ERROR;
+      }
+    }
+    return NPERR_GENERIC_ERROR;
+  }
+
+#ifndef NP_NO_QUICKDRAW
+  case NPNVsupportsQuickDrawBool: {
+    *(NPBool*)result = false;
+
+    return NPERR_NO_ERROR;
+  }
+#endif
+
+  case NPNVsupportsCoreGraphicsBool: {
+    *(NPBool*)result = true;
+
+    return NPERR_NO_ERROR;
+  }
+
+  case NPNVsupportsCoreAnimationBool: {
+    *(NPBool*)result = true;
+
+    return NPERR_NO_ERROR;
+  }
+
+  case NPNVsupportsInvalidatingCoreAnimationBool: {
+    *(NPBool*)result = true;
+
+    return NPERR_NO_ERROR;
+  }
+
+  case NPNVsupportsCompositingCoreAnimationPluginsBool: {
+    *(NPBool*)result = PR_TRUE;
+
+    return NPERR_NO_ERROR;
+  }
+
+#ifndef NP_NO_CARBON
+  case NPNVsupportsCarbonBool: {
+    *(NPBool*)result = false;
+
+    return NPERR_NO_ERROR;
+  }
+#endif
+  case NPNVsupportsCocoaBool: {
+    *(NPBool*)result = true;
+
+    return NPERR_NO_ERROR;
+  }
+
+  case NPNVsupportsUpdatedCocoaTextInputBool: {
+    *(NPBool*)result = true;
+    return NPERR_NO_ERROR;
+  }
+#endif
+
+#if defined(XP_MACOSX) || defined(XP_WIN)
   case NPNVcontentsScaleFactor: {
     nsNPAPIPluginInstance *inst =
       (nsNPAPIPluginInstance *) (npp ? npp->ndata : nullptr);
@@ -1964,8 +2051,16 @@ _setvalue(NPP npp, NPPVariable variable, void *result)
     // actual pointer value is checked rather than its content
     // when passing booleans
     case NPPVpluginWindowBool: {
+#ifdef XP_MACOSX
+      // This setting doesn't apply to OS X (only to Windows and Unix/Linux).
+      // See https://developer.mozilla.org/En/NPN_SetValue#section_5.  Return
+      // NPERR_NO_ERROR here to conform to other browsers' behavior on OS X
+      // (e.g. Safari and Opera).
+      return NPERR_NO_ERROR;
+#else
       NPBool bWindowless = (result == nullptr);
       return inst->SetWindowless(bWindowless);
+#endif
     }
     case NPPVpluginTransparentBool: {
       NPBool bTransparent = (result != nullptr);
@@ -2050,6 +2145,18 @@ _setvalue(NPP npp, NPPVariable variable, void *result)
       }
     }
 
+#ifdef XP_MACOSX
+    case NPPVpluginEventModel: {
+      if (inst) {
+        inst->SetEventModel((NPEventModel)NS_PTR_TO_INT32(result));
+        return NPERR_NO_ERROR;
+      }
+      else {
+        return NPERR_GENERIC_ERROR;
+      }
+    }
+#endif
+
     default:
       return NPERR_GENERIC_ERROR;
   }
diff --git a/dom/plugins/base/nsNPAPIPlugin.h b/dom/plugins/base/nsNPAPIPlugin.h
index 7727bf77fb..96e630b629 100644
--- a/dom/plugins/base/nsNPAPIPlugin.h
+++ b/dom/plugins/base/nsNPAPIPlugin.h
@@ -45,6 +45,10 @@ public:
   // PluginFuncs() can't fail but results are only valid if GetLibrary() succeeds
   NPPluginFuncs* PluginFuncs();
 
+#if defined(XP_MACOSX) && !defined(__LP64__)
+  void SetPluginRefNum(short aRefNum);
+#endif
+
   // The IPC mechanism notifies the nsNPAPIPlugin if the plugin
   // crashes and is no longer usable. pluginDumpID/browserDumpID are
   // the IDs of respective minidumps that were written, or empty if no
diff --git a/dom/plugins/base/nsNPAPIPluginInstance.cpp b/dom/plugins/base/nsNPAPIPluginInstance.cpp
index 6e35bf3662..170f42b28e 100644
--- a/dom/plugins/base/nsNPAPIPluginInstance.cpp
+++ b/dom/plugins/base/nsNPAPIPluginInstance.cpp
@@ -60,6 +60,9 @@ nsNPAPIPluginInstance::nsNPAPIPluginInstance()
   , mPlugin(nullptr)
   , mMIMEType(nullptr)
   , mOwner(nullptr)
+#ifdef XP_MACOSX
+  , mCurrentPluginEvent(nullptr)
+#endif
   , mHaveJavaC2PJSObjectQuirk(false)
   , mCachedParamLength(0)
   , mCachedParamNames(nullptr)
@@ -500,6 +503,9 @@ nsresult nsNPAPIPluginInstance::HandleEvent(void* event, int16_t* result,
   int16_t tmpResult = kNPEventNotHandled;
 
   if (pluginFunctions->event) {
+#ifdef XP_MACOSX
+    mCurrentPluginEvent = event;
+#endif
 #if defined(XP_WIN)
     NS_TRY_SAFE_CALL_RETURN(tmpResult, (*pluginFunctions->event)(&mNPP, event), this,
                             aSafeToReenterGecko);
@@ -513,6 +519,9 @@ nsresult nsNPAPIPluginInstance::HandleEvent(void* event, int16_t* result,
 
     if (result)
       *result = tmpResult;
+#ifdef XP_MACOSX
+    mCurrentPluginEvent = nullptr;
+#endif
   }
 
   return NS_OK;
@@ -608,6 +617,19 @@ void nsNPAPIPluginInstance::RedrawPlugin()
   mOwner->RedrawPlugin();
 }
 
+#if defined(XP_MACOSX)
+void nsNPAPIPluginInstance::SetEventModel(NPEventModel aModel)
+{
+  // the event model needs to be set for the object frame immediately
+  if (!mOwner) {
+    NS_WARNING("Trying to set event model without a plugin instance owner!");
+    return;
+  }
+
+  mOwner->SetEventModel(aModel);
+}
+#endif
+
 nsresult nsNPAPIPluginInstance::GetDrawingModel(int32_t* aModel)
 {
   *aModel = (int32_t)mDrawingModel;
@@ -616,14 +638,24 @@ nsresult nsNPAPIPluginInstance::GetDrawingModel(int32_t* aModel)
 
 nsresult nsNPAPIPluginInstance::IsRemoteDrawingCoreAnimation(bool* aDrawing)
 {
-  /** Mac Stub **/
+#ifdef XP_MACOSX
+  if (!mPlugin)
+      return NS_ERROR_FAILURE;
+
+  PluginLibrary* library = mPlugin->GetLibrary();
+  if (!library)
+      return NS_ERROR_FAILURE;
+
+  return library->IsRemoteDrawingCoreAnimation(&mNPP, aDrawing);
+#else
   return NS_ERROR_FAILURE;
+#endif
 }
 
 nsresult
 nsNPAPIPluginInstance::ContentsScaleFactorChanged(double aContentsScaleFactor)
 {
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   if (!mPlugin)
       return NS_ERROR_FAILURE;
 
@@ -700,7 +732,12 @@ nsNPAPIPluginInstance::ShouldCache()
 nsresult
 nsNPAPIPluginInstance::IsWindowless(bool* isWindowless)
 {
+#ifdef XP_MACOSX
+  // All OS X plugins are windowless.
+  *isWindowless = true;
+#else
   *isWindowless = mWindowless;
+#endif
   return NS_OK;
 }
 
diff --git a/dom/plugins/base/nsNPAPIPluginInstance.h b/dom/plugins/base/nsNPAPIPluginInstance.h
index c3272e0a87..48e62517de 100644
--- a/dom/plugins/base/nsNPAPIPluginInstance.h
+++ b/dom/plugins/base/nsNPAPIPluginInstance.h
@@ -34,6 +34,12 @@ class nsPluginInstanceOwner;
 const NPDrawingModel kDefaultDrawingModel = NPDrawingModelSyncWin;
 #elif defined(MOZ_X11)
 const NPDrawingModel kDefaultDrawingModel = NPDrawingModelSyncX;
+#elif defined(XP_MACOSX)
+#ifndef NP_NO_QUICKDRAW
+const NPDrawingModel kDefaultDrawingModel = NPDrawingModelQuickDraw; // Not supported
+#else
+const NPDrawingModel kDefaultDrawingModel = NPDrawingModelCoreGraphics;
+#endif
 #else
 const NPDrawingModel kDefaultDrawingModel = static_cast<NPDrawingModel>(0);
 #endif
@@ -140,6 +146,13 @@ public:
 
   void SetDrawingModel(NPDrawingModel aModel);
   void RedrawPlugin();
+#ifdef XP_MACOSX
+  void SetEventModel(NPEventModel aModel);
+
+  void* GetCurrentEvent() {
+    return mCurrentPluginEvent;
+  }
+#endif
 
   nsresult NewStreamListener(const char* aURL, void* notifyData,
                              nsNPAPIPluginStreamListener** listener);
@@ -278,6 +291,11 @@ private:
 
   nsTArray<nsNPAPITimer*> mTimers;
 
+#ifdef XP_MACOSX
+  // non-null during a HandleEvent call
+  void* mCurrentPluginEvent;
+#endif
+
   // Timestamp for the last time this plugin was stopped.
   // This is only valid when the plugin is actually stopped!
   mozilla::TimeStamp mStopTime;
diff --git a/dom/plugins/base/nsPluginHost.cpp b/dom/plugins/base/nsPluginHost.cpp
index b36bf96331..c9c1b71fe0 100644
--- a/dom/plugins/base/nsPluginHost.cpp
+++ b/dom/plugins/base/nsPluginHost.cpp
@@ -33,6 +33,9 @@
 #include "nsProtocolProxyService.h"
 #include "nsIStreamConverterService.h"
 #include "nsIFile.h"
+#if defined(XP_MACOSX)
+#include "nsILocalFileMac.h"
+#endif
 #include "nsISeekableStream.h"
 #include "nsNetUtil.h"
 #include "nsIFileStreams.h"
@@ -1921,7 +1924,19 @@ int64_t GetPluginLastModifiedTime(const nsCOMPtr<nsIFile>& localfile)
 {
   PRTime fileModTime = 0;
 
+#if defined(XP_MACOSX)
+  // On OS X the date of a bundle's "contents" (i.e. of its Info.plist file)
+  // is a much better guide to when it was last modified than the date of
+  // its package directory.  See bug 313700.
+  nsCOMPtr<nsILocalFileMac> localFileMac = do_QueryInterface(localfile);
+  if (localFileMac) {
+    localFileMac->GetBundleContentsLastModifiedTime(&fileModTime);
+  } else {
+    localfile->GetLastModifiedTime(&fileModTime);
+  }
+#else
   localfile->GetLastModifiedTime(&fileModTime);
+#endif
 
   return fileModTime;
 }
diff --git a/dom/plugins/base/nsPluginInstanceOwner.cpp b/dom/plugins/base/nsPluginInstanceOwner.cpp
index 60a9bc0caa..0d4dc68ccc 100644
--- a/dom/plugins/base/nsPluginInstanceOwner.cpp
+++ b/dom/plugins/base/nsPluginInstanceOwner.cpp
@@ -77,6 +77,12 @@ static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
 #include "mozilla/widget/WinMessages.h"
 #endif // #ifdef XP_WIN
 
+#ifdef XP_MACOSX
+#include "ComplexTextInputPanel.h"
+#include "nsIDOMXULDocument.h"
+#include "nsIDOMXULCommandDispatcher.h"
+#endif
+
 #ifdef MOZ_WIDGET_GTK
 #include <gdk/gdk.h>
 #include <gtk/gtk.h>
@@ -223,13 +229,27 @@ nsPluginInstanceOwner::EndUpdateBackground(const nsIntRect& aRect)
 bool
 nsPluginInstanceOwner::UseAsyncRendering()
 {
+#ifdef XP_MACOSX
+  if (mUseAsyncRendering) {
+    return true;
+  }
+#endif
+
   bool isOOP;
   bool result = (mInstance &&
           NS_SUCCEEDED(mInstance->GetIsOOP(&isOOP)) && isOOP
+#ifndef XP_MACOSX
           && (!mPluginWindow ||
            mPluginWindow->type == NPWindowTypeDrawable)
+#endif
           );
 
+#ifdef XP_MACOSX
+  if (result) {
+    mUseAsyncRendering = true;
+  }
+#endif
+
   return result;
 }
 
@@ -255,6 +275,13 @@ nsPluginInstanceOwner::nsPluginInstanceOwner()
 
   mPluginFrame = nullptr;
   mWidgetCreationComplete = false;
+#ifdef XP_MACOSX
+  mSentInitialTopLevelWindowEvent = false;
+  mLastWindowIsActive = false;
+  mLastContentFocused = false;
+  mLastScaleFactor = 1.0;
+  mShouldBlurOnActivate = false;
+#endif
   mLastCSSZoomFactor = 1.0;
   mContentFocused = false;
   mWidgetVisible = true;
@@ -262,6 +289,16 @@ nsPluginInstanceOwner::nsPluginInstanceOwner()
   mPluginDocumentActiveState = true;
   mLastMouseDownButtonType = -1;
 
+#ifdef XP_MACOSX
+#ifndef NP_NO_CARBON
+  // We don't support Carbon, but it is still the default model for i386 NPAPI.
+  mEventModel = NPEventModelCarbon;
+#else
+  mEventModel = NPEventModelCocoa;
+#endif
+  mUseAsyncRendering = false;
+#endif
+
   mWaitingForPaint = false;
 
 #ifdef XP_WIN
@@ -494,6 +531,15 @@ NS_IMETHODIMP nsPluginInstanceOwner::InvalidateRect(NPRect *invalidRect)
   if (!mPluginFrame || !invalidRect || !mWidgetVisible)
     return NS_ERROR_FAILURE;
 
+#ifdef XP_MACOSX
+  // Each time an asynchronously-drawing plugin sends a new surface to display,
+  // the image in the ImageContainer is updated and InvalidateRect is called.
+  // There are different side effects for (sync) Android plugins.
+  RefPtr<ImageContainer> container;
+  mInstance->GetImageContainer(getter_AddRefs(container));
+#endif
+
+#ifndef XP_MACOSX
   // Silverlight calls invalidate for windowed plugins so this needs to work.
   if (mWidget) {
     mWidget->Invalidate(
@@ -507,6 +553,7 @@ NS_IMETHODIMP nsPluginInstanceOwner::InvalidateRect(NPRect *invalidRect)
       return NS_OK;
     }
   }
+#endif
 
   nsIntRect rect(invalidRect->left,
                  invalidRect->top,
@@ -917,14 +964,252 @@ nsPluginInstanceOwner::OnWindowedPluginKeyEvent(
 
 NS_IMETHODIMP nsPluginInstanceOwner::SetEventModel(int32_t eventModel)
 {
+#ifdef XP_MACOSX
+  mEventModel = static_cast<NPEventModel>(eventModel);
+  return NS_OK;
+#else
   return NS_ERROR_NOT_IMPLEMENTED;
+#endif
+}
+
+#ifdef XP_MACOSX
+NPBool nsPluginInstanceOwner::ConvertPointPuppet(PuppetWidget *widget,
+                                                 nsPluginFrame* pluginFrame,
+                                                 double sourceX, double sourceY,
+                                                 NPCoordinateSpace sourceSpace,
+                                                 double *destX, double *destY,
+                                                 NPCoordinateSpace destSpace)
+{
+  NS_ENSURE_TRUE(widget && widget->GetOwningTabChild() && pluginFrame, false);
+  // Caller has to want a result.
+  NS_ENSURE_TRUE(destX || destY, false);
+
+  if (sourceSpace == destSpace) {
+    if (destX) {
+      *destX = sourceX;
+    }
+    if (destY) {
+      *destY = sourceY;
+    }
+    return true;
+  }
+
+  nsPresContext* presContext = pluginFrame->PresContext();
+  double scaleFactor = double(nsPresContext::AppUnitsPerCSSPixel())/
+    presContext->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom();
+
+  PuppetWidget *puppetWidget = static_cast<PuppetWidget*>(widget);
+  PuppetWidget *rootWidget = static_cast<PuppetWidget*>(widget->GetTopLevelWidget());
+  if (!rootWidget) {
+    return false;
+  }
+  nsPoint chromeSize = AsNsPoint(rootWidget->GetChromeDimensions()) / scaleFactor;
+  nsIntSize intScreenDims = rootWidget->GetScreenDimensions();
+  nsSize screenDims = nsSize(intScreenDims.width / scaleFactor,
+                             intScreenDims.height / scaleFactor);
+  int32_t screenH = screenDims.height;
+  nsPoint windowPosition = AsNsPoint(rootWidget->GetWindowPosition()) / scaleFactor;
+
+  // Window size is tab size + chrome size.
+  LayoutDeviceIntRect tabContentBounds = puppetWidget->GetBounds();
+  tabContentBounds.ScaleInverseRoundOut(scaleFactor);
+  int32_t windowH = tabContentBounds.height + int(chromeSize.y);
+
+  nsPoint pluginPosition = AsNsPoint(pluginFrame->GetScreenRect().TopLeft());
+
+  // Convert (sourceX, sourceY) to 'real' (not PuppetWidget) screen space.
+  // In OSX, the Y-axis increases upward, which is the reverse of ours.
+  // We want OSX coordinates for window and screen so those equations are swapped.
+  nsPoint sourcePoint(sourceX, sourceY);
+  nsPoint screenPoint;
+  switch (sourceSpace) {
+    case NPCoordinateSpacePlugin:
+      screenPoint = sourcePoint + pluginPosition +
+        pluginFrame->GetContentRectRelativeToSelf().TopLeft() / nsPresContext::AppUnitsPerCSSPixel();
+      break;
+    case NPCoordinateSpaceWindow:
+      screenPoint = nsPoint(sourcePoint.x, windowH-sourcePoint.y) +
+        windowPosition;
+      break;
+    case NPCoordinateSpaceFlippedWindow:
+      screenPoint = sourcePoint + windowPosition;
+      break;
+    case NPCoordinateSpaceScreen:
+      screenPoint = nsPoint(sourcePoint.x, screenH-sourcePoint.y);
+      break;
+    case NPCoordinateSpaceFlippedScreen:
+      screenPoint = sourcePoint;
+      break;
+    default:
+      return false;
+  }
+
+  // Convert from screen to dest space.
+  nsPoint destPoint;
+  switch (destSpace) {
+    case NPCoordinateSpacePlugin:
+      destPoint = screenPoint - pluginPosition -
+        pluginFrame->GetContentRectRelativeToSelf().TopLeft() / nsPresContext::AppUnitsPerCSSPixel();
+      break;
+    case NPCoordinateSpaceWindow:
+      destPoint = screenPoint - windowPosition;
+      destPoint.y = windowH - destPoint.y;
+      break;
+    case NPCoordinateSpaceFlippedWindow:
+      destPoint = screenPoint - windowPosition;
+      break;
+    case NPCoordinateSpaceScreen:
+      destPoint = nsPoint(screenPoint.x, screenH-screenPoint.y);
+      break;
+    case NPCoordinateSpaceFlippedScreen:
+      destPoint = screenPoint;
+      break;
+    default:
+      return false;
+  }
+
+  if (destX) {
+    *destX = destPoint.x;
+  }
+  if (destY) {
+    *destY = destPoint.y;
+  }
+
+  return true;
 }
 
+NPBool nsPluginInstanceOwner::ConvertPointNoPuppet(nsIWidget *widget,
+                                                   nsPluginFrame* pluginFrame,
+                                                   double sourceX, double sourceY,
+                                                   NPCoordinateSpace sourceSpace,
+                                                   double *destX, double *destY,
+                                                   NPCoordinateSpace destSpace)
+{
+  NS_ENSURE_TRUE(widget && pluginFrame, false);
+  // Caller has to want a result.
+  NS_ENSURE_TRUE(destX || destY, false);
+
+  if (sourceSpace == destSpace) {
+    if (destX) {
+      *destX = sourceX;
+    }
+    if (destY) {
+      *destY = sourceY;
+    }
+    return true;
+  }
+
+  nsPresContext* presContext = pluginFrame->PresContext();
+  double scaleFactor = double(nsPresContext::AppUnitsPerCSSPixel())/
+    presContext->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom();
+
+  nsCOMPtr<nsIScreenManager> screenMgr = do_GetService("@mozilla.org/gfx/screenmanager;1");
+  if (!screenMgr) {
+    return false;
+  }
+  nsCOMPtr<nsIScreen> screen;
+  screenMgr->ScreenForNativeWidget(widget->GetNativeData(NS_NATIVE_WINDOW), getter_AddRefs(screen));
+  if (!screen) {
+    return false;
+  }
+
+  int32_t screenX, screenY, screenWidth, screenHeight;
+  screen->GetRect(&screenX, &screenY, &screenWidth, &screenHeight);
+  screenHeight /= scaleFactor;
+
+  LayoutDeviceIntRect windowScreenBounds = widget->GetScreenBounds();
+  windowScreenBounds.ScaleInverseRoundOut(scaleFactor);
+  int32_t windowX = windowScreenBounds.x;
+  int32_t windowY = windowScreenBounds.y;
+  int32_t windowHeight = windowScreenBounds.height;
+
+  nsIntRect pluginScreenRect = pluginFrame->GetScreenRect();
+
+  double screenXGecko, screenYGecko;
+  switch (sourceSpace) {
+    case NPCoordinateSpacePlugin:
+      screenXGecko = pluginScreenRect.x + sourceX;
+      screenYGecko = pluginScreenRect.y + sourceY;
+      break;
+    case NPCoordinateSpaceWindow:
+      screenXGecko = windowX + sourceX;
+      screenYGecko = windowY + (windowHeight - sourceY);
+      break;
+    case NPCoordinateSpaceFlippedWindow:
+      screenXGecko = windowX + sourceX;
+      screenYGecko = windowY + sourceY;
+      break;
+    case NPCoordinateSpaceScreen:
+      screenXGecko = sourceX;
+      screenYGecko = screenHeight - sourceY;
+      break;
+    case NPCoordinateSpaceFlippedScreen:
+      screenXGecko = sourceX;
+      screenYGecko = sourceY;
+      break;
+    default:
+      return false;
+  }
+
+  double destXCocoa, destYCocoa;
+  switch (destSpace) {
+    case NPCoordinateSpacePlugin:
+      destXCocoa = screenXGecko - pluginScreenRect.x;
+      destYCocoa = screenYGecko - pluginScreenRect.y;
+      break;
+    case NPCoordinateSpaceWindow:
+      destXCocoa = screenXGecko - windowX;
+      destYCocoa = windowHeight - (screenYGecko - windowY);
+      break;
+    case NPCoordinateSpaceFlippedWindow:
+      destXCocoa = screenXGecko - windowX;
+      destYCocoa = screenYGecko - windowY;
+      break;
+    case NPCoordinateSpaceScreen:
+      destXCocoa = screenXGecko;
+      destYCocoa = screenHeight - screenYGecko;
+      break;
+    case NPCoordinateSpaceFlippedScreen:
+      destXCocoa = screenXGecko;
+      destYCocoa = screenYGecko;
+      break;
+    default:
+      return false;
+  }
+
+  if (destX) {
+    *destX = destXCocoa;
+  }
+  if (destY) {
+    *destY = destYCocoa;
+  }
+
+  return true;
+}
+#endif // XP_MACOSX
+
 NPBool nsPluginInstanceOwner::ConvertPoint(double sourceX, double sourceY, NPCoordinateSpace sourceSpace,
                                            double *destX, double *destY, NPCoordinateSpace destSpace)
 {
-  /** Mac Stub **/
+#ifdef XP_MACOSX
+  if (!mPluginFrame) {
+    return false;
+  }
+
+  MOZ_ASSERT(mPluginFrame->GetNearestWidget());
+
+  if (nsIWidget::UsePuppetWidgets()) {
+    return ConvertPointPuppet(static_cast<PuppetWidget*>(mPluginFrame->GetNearestWidget()),
+                               mPluginFrame, sourceX, sourceY, sourceSpace,
+                               destX, destY, destSpace);
+  }
+
+  return ConvertPointNoPuppet(mPluginFrame->GetNearestWidget(),
+                              mPluginFrame, sourceX, sourceY, sourceSpace,
+                              destX, destY, destSpace);
+#else
   return false;
+#endif
 }
 
 NPError nsPluginInstanceOwner::InitAsyncSurface(NPSize *size, NPImageFormat format,
@@ -968,7 +1253,133 @@ void nsPluginInstanceOwner::GetParameters(nsTArray<MozPluginParameter>& paramete
   loadingContent->GetPluginParameters(parameters);
 }
 
-#if defined(XP_WIN)
+#ifdef XP_MACOSX
+
+static void InitializeNPCocoaEvent(NPCocoaEvent* event)
+{
+  memset(event, 0, sizeof(NPCocoaEvent));
+}
+
+NPDrawingModel nsPluginInstanceOwner::GetDrawingModel()
+{
+#ifndef NP_NO_QUICKDRAW
+  // We don't support the Quickdraw drawing model any more but it's still
+  // the default model for i386 per NPAPI.
+  NPDrawingModel drawingModel = NPDrawingModelQuickDraw;
+#else
+  NPDrawingModel drawingModel = NPDrawingModelCoreGraphics;
+#endif
+
+  if (!mInstance)
+    return drawingModel;
+
+  mInstance->GetDrawingModel((int32_t*)&drawingModel);
+  return drawingModel;
+}
+
+bool nsPluginInstanceOwner::IsRemoteDrawingCoreAnimation()
+{
+  if (!mInstance)
+    return false;
+
+  bool coreAnimation;
+  if (!NS_SUCCEEDED(mInstance->IsRemoteDrawingCoreAnimation(&coreAnimation)))
+    return false;
+
+  return coreAnimation;
+}
+
+NPEventModel nsPluginInstanceOwner::GetEventModel()
+{
+  return mEventModel;
+}
+
+#define DEFAULT_REFRESH_RATE 20 // 50 FPS
+
+nsCOMPtr<nsITimer>               *nsPluginInstanceOwner::sCATimer = nullptr;
+nsTArray<nsPluginInstanceOwner*> *nsPluginInstanceOwner::sCARefreshListeners = nullptr;
+
+void nsPluginInstanceOwner::CARefresh(nsITimer *aTimer, void *aClosure) {
+  if (!sCARefreshListeners) {
+    return;
+  }
+  for (size_t i = 0; i < sCARefreshListeners->Length(); i++) {
+    nsPluginInstanceOwner* instanceOwner = (*sCARefreshListeners)[i];
+    NPWindow *window;
+    instanceOwner->GetWindow(window);
+    if (!window) {
+      continue;
+    }
+    NPRect r;
+    r.left = 0;
+    r.top = 0;
+    r.right = window->width;
+    r.bottom = window->height;
+    instanceOwner->InvalidateRect(&r);
+  }
+}
+
+void nsPluginInstanceOwner::AddToCARefreshTimer() {
+  if (!mInstance) {
+    return;
+  }
+
+  // Flash invokes InvalidateRect for us.
+  const char* mime = nullptr;
+  if (NS_SUCCEEDED(mInstance->GetMIMEType(&mime)) && mime &&
+      nsPluginHost::GetSpecialType(nsDependentCString(mime)) ==
+      nsPluginHost::eSpecialType_Flash) {
+    return;
+  }
+
+  if (!sCARefreshListeners) {
+    sCARefreshListeners = new nsTArray<nsPluginInstanceOwner*>();
+  }
+
+  if (sCARefreshListeners->Contains(this)) {
+    return;
+  }
+
+  sCARefreshListeners->AppendElement(this);
+
+  if (!sCATimer) {
+    sCATimer = new nsCOMPtr<nsITimer>();
+  }
+
+  if (sCARefreshListeners->Length() == 1) {
+    *sCATimer = do_CreateInstance("@mozilla.org/timer;1");
+    (*sCATimer)->InitWithFuncCallback(CARefresh, nullptr,
+                   DEFAULT_REFRESH_RATE, nsITimer::TYPE_REPEATING_SLACK);
+  }
+}
+
+void nsPluginInstanceOwner::RemoveFromCARefreshTimer() {
+  if (!sCARefreshListeners || sCARefreshListeners->Contains(this) == false) {
+    return;
+  }
+
+  sCARefreshListeners->RemoveElement(this);
+
+  if (sCARefreshListeners->Length() == 0) {
+    if (sCATimer) {
+      (*sCATimer)->Cancel();
+      delete sCATimer;
+      sCATimer = nullptr;
+    }
+    delete sCARefreshListeners;
+    sCARefreshListeners = nullptr;
+  }
+}
+
+void nsPluginInstanceOwner::SetPluginPort()
+{
+  void* pluginPort = GetPluginPort();
+  if (!pluginPort || !mPluginWindow)
+    return;
+  mPluginWindow->window = pluginPort;
+}
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
 nsresult nsPluginInstanceOwner::ContentsScaleFactorChanged(double aContentsScaleFactor)
 {
   if (!mInstance) {
@@ -987,6 +1398,11 @@ nsPluginInstanceOwner::GetEventloopNestingLevel()
   uint32_t currentLevel = 0;
   if (appShell) {
     appShell->GetEventloopNestingLevel(&currentLevel);
+#ifdef XP_MACOSX
+    // Cocoa widget code doesn't process UI events through the normal
+    // appshell event loop, so it needs an additional count here.
+    currentLevel++;
+#endif
   }
 
   // No idea how this happens... but Linux doesn't consistently
@@ -1011,11 +1427,15 @@ void
 nsPluginInstanceOwner::NotifyHostCreateWidget()
 {
   mPluginHost->CreateWidget(this);
+#ifdef XP_MACOSX
+  FixUpPluginWindow(ePluginPaintEnable);
+#else
   if (mPluginFrame) {
     mPluginFrame->InvalidateFrame();
   } else {
     CallSetWindow();
   }
+#endif
 }
 
 void
@@ -1037,10 +1457,12 @@ nsPluginInstanceOwner::NotifyDestroyPending()
 
 nsresult nsPluginInstanceOwner::DispatchFocusToPlugin(nsIDOMEvent* aFocusEvent)
 {
+#ifndef XP_MACOSX
   if (!mPluginWindow || (mPluginWindow->type == NPWindowTypeWindow)) {
     // continue only for cases without child window
     return aFocusEvent->PreventDefault(); // consume event
   }
+#endif
 
   WidgetEvent* theEvent = aFocusEvent->WidgetEventPtr();
   if (theEvent) {
@@ -1058,6 +1480,9 @@ nsresult nsPluginInstanceOwner::DispatchFocusToPlugin(nsIDOMEvent* aFocusEvent)
 
 nsresult nsPluginInstanceOwner::ProcessKeyPress(nsIDOMEvent* aKeyEvent)
 {
+#ifdef XP_MACOSX
+  return DispatchKeyToPlugin(aKeyEvent);
+#else
   if (SendNativeEvents())
     DispatchKeyToPlugin(aKeyEvent);
 
@@ -1068,13 +1493,16 @@ nsresult nsPluginInstanceOwner::ProcessKeyPress(nsIDOMEvent* aKeyEvent)
     aKeyEvent->StopPropagation();
   }
   return NS_OK;
+#endif
 }
 
 nsresult nsPluginInstanceOwner::DispatchKeyToPlugin(nsIDOMEvent* aKeyEvent)
 {
+#if !defined(XP_MACOSX)
   if (!mPluginWindow || (mPluginWindow->type == NPWindowTypeWindow))
     return aKeyEvent->PreventDefault(); // consume event
   // continue only for cases without child window
+#endif
 
   if (mInstance) {
     WidgetKeyboardEvent* keyEvent =
@@ -1094,9 +1522,11 @@ nsresult nsPluginInstanceOwner::DispatchKeyToPlugin(nsIDOMEvent* aKeyEvent)
 nsresult
 nsPluginInstanceOwner::ProcessMouseDown(nsIDOMEvent* aMouseEvent)
 {
+#if !defined(XP_MACOSX)
   if (!mPluginWindow || (mPluginWindow->type == NPWindowTypeWindow))
     return aMouseEvent->PreventDefault(); // consume event
   // continue only for cases without child window
+#endif
 
   // if the plugin is windowless, we need to set focus ourselves
   // otherwise, we might not get key events
@@ -1126,9 +1556,11 @@ nsPluginInstanceOwner::ProcessMouseDown(nsIDOMEvent* aMouseEvent)
 nsresult nsPluginInstanceOwner::DispatchMouseToPlugin(nsIDOMEvent* aMouseEvent,
                                                       bool aAllowPropagate)
 {
+#if !defined(XP_MACOSX)
   if (!mPluginWindow || (mPluginWindow->type == NPWindowTypeWindow))
     return aMouseEvent->PreventDefault(); // consume event
   // continue only for cases without child window
+#endif
   // don't send mouse events if we are hidden
   if (!mWidgetVisible)
     return NS_OK;
@@ -1338,6 +1770,22 @@ nsPluginInstanceOwner::HandleEvent(nsIDOMEvent* aEvent)
   nsAutoString eventType;
   aEvent->GetType(eventType);
 
+#ifdef XP_MACOSX
+  if (eventType.EqualsLiteral("activate") ||
+      eventType.EqualsLiteral("deactivate")) {
+    WindowFocusMayHaveChanged();
+    return NS_OK;
+  }
+  if (eventType.EqualsLiteral("MozPerformDelayedBlur")) {
+    if (mShouldBlurOnActivate) {
+      WidgetGUIEvent blurEvent(true, eBlur, nullptr);
+      ProcessEvent(blurEvent);
+      mShouldBlurOnActivate = false;
+    }
+    return NS_OK;
+  }
+#endif
+
   if (eventType.EqualsLiteral("focus")) {
     mContentFocused = true;
     return DispatchFocusToPlugin(aEvent);
@@ -1400,6 +1848,191 @@ static unsigned int XInputEventState(const WidgetInputEvent& anEvent)
 }
 #endif
 
+#ifdef XP_MACOSX
+
+// Returns whether or not content is the content that is or would be
+// focused if the top-level chrome window was active.
+static bool
+ContentIsFocusedWithinWindow(nsIContent* aContent)
+{
+  nsPIDOMWindowOuter* outerWindow = aContent->OwnerDoc()->GetWindow();
+  if (!outerWindow) {
+    return false;
+  }
+
+  nsPIDOMWindowOuter* rootWindow = outerWindow->GetPrivateRoot();
+  if (!rootWindow) {
+    return false;
+  }
+
+  nsFocusManager* fm = nsFocusManager::GetFocusManager();
+  if (!fm) {
+    return false;
+  }
+
+  nsCOMPtr<nsPIDOMWindowOuter> focusedFrame;
+  nsCOMPtr<nsIContent> focusedContent = fm->GetFocusedDescendant(rootWindow, true, getter_AddRefs(focusedFrame));
+  return (focusedContent.get() == aContent);
+}
+
+static NPCocoaEventType
+CocoaEventTypeForEvent(const WidgetGUIEvent& anEvent, nsIFrame* aObjectFrame)
+{
+  const NPCocoaEvent* event = static_cast<const NPCocoaEvent*>(anEvent.mPluginEvent);
+  if (event) {
+    return event->type;
+  }
+
+  switch (anEvent.mMessage) {
+    case eMouseOver:
+      return NPCocoaEventMouseEntered;
+    case eMouseOut:
+      return NPCocoaEventMouseExited;
+    case eMouseMove: {
+      // We don't know via information on events from the widget code whether or not
+      // we're dragging. The widget code just generates mouse move events from native
+      // drag events. If anybody is capturing, this is a drag event.
+      if (nsIPresShell::GetCapturingContent()) {
+        return NPCocoaEventMouseDragged;
+      }
+
+      return NPCocoaEventMouseMoved;
+    }
+    case eMouseDown:
+      return NPCocoaEventMouseDown;
+    case eMouseUp:
+      return NPCocoaEventMouseUp;
+    case eKeyDown:
+      return NPCocoaEventKeyDown;
+    case eKeyUp:
+      return NPCocoaEventKeyUp;
+    case eFocus:
+    case eBlur:
+      return NPCocoaEventFocusChanged;
+    case eLegacyMouseLineOrPageScroll:
+      return NPCocoaEventScrollWheel;
+    default:
+      return (NPCocoaEventType)0;
+  }
+}
+
+static NPCocoaEvent
+TranslateToNPCocoaEvent(WidgetGUIEvent* anEvent, nsIFrame* aObjectFrame)
+{
+  NPCocoaEvent cocoaEvent;
+  InitializeNPCocoaEvent(&cocoaEvent);
+  cocoaEvent.type = CocoaEventTypeForEvent(*anEvent, aObjectFrame);
+
+  if (anEvent->mMessage == eMouseMove ||
+      anEvent->mMessage == eMouseDown ||
+      anEvent->mMessage == eMouseUp ||
+      anEvent->mMessage == eLegacyMouseLineOrPageScroll ||
+      anEvent->mMessage == eMouseOver ||
+      anEvent->mMessage == eMouseOut)
+  {
+    nsPoint pt = nsLayoutUtils::GetEventCoordinatesRelativeTo(anEvent, aObjectFrame) -
+                 aObjectFrame->GetContentRectRelativeToSelf().TopLeft();
+    nsPresContext* presContext = aObjectFrame->PresContext();
+    // Plugin event coordinates need to be translated from device pixels
+    // into "display pixels" in HiDPI modes.
+    double scaleFactor = double(nsPresContext::AppUnitsPerCSSPixel())/
+      aObjectFrame->PresContext()->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom();
+    size_t intScaleFactor = ceil(scaleFactor);
+    nsIntPoint ptPx(presContext->AppUnitsToDevPixels(pt.x) / intScaleFactor,
+                    presContext->AppUnitsToDevPixels(pt.y) / intScaleFactor);
+    cocoaEvent.data.mouse.pluginX = double(ptPx.x);
+    cocoaEvent.data.mouse.pluginY = double(ptPx.y);
+  }
+
+  switch (anEvent->mMessage) {
+    case eMouseDown:
+    case eMouseUp: {
+      WidgetMouseEvent* mouseEvent = anEvent->AsMouseEvent();
+      if (mouseEvent) {
+        switch (mouseEvent->button) {
+          case WidgetMouseEvent::eLeftButton:
+            cocoaEvent.data.mouse.buttonNumber = 0;
+            break;
+          case WidgetMouseEvent::eRightButton:
+            cocoaEvent.data.mouse.buttonNumber = 1;
+            break;
+          case WidgetMouseEvent::eMiddleButton:
+            cocoaEvent.data.mouse.buttonNumber = 2;
+            break;
+          default:
+            NS_WARNING("Mouse button we don't know about?");
+        }
+        cocoaEvent.data.mouse.clickCount = mouseEvent->mClickCount;
+      } else {
+        NS_WARNING("eMouseUp/DOWN is not a WidgetMouseEvent?");
+      }
+      break;
+    }
+    case eLegacyMouseLineOrPageScroll: {
+      WidgetWheelEvent* wheelEvent = anEvent->AsWheelEvent();
+      if (wheelEvent) {
+        cocoaEvent.data.mouse.deltaX = wheelEvent->mLineOrPageDeltaX;
+        cocoaEvent.data.mouse.deltaY = wheelEvent->mLineOrPageDeltaY;
+      } else {
+        NS_WARNING("eLegacyMouseLineOrPageScroll is not a WidgetWheelEvent? "
+                   "(could be, haven't checked)");
+      }
+      break;
+    }
+    case eKeyDown:
+    case eKeyUp:
+    {
+      WidgetKeyboardEvent* keyEvent = anEvent->AsKeyboardEvent();
+
+      // That keyEvent->mPluginTextEventString is non-empty is a signal that we should
+      // create a text event for the plugin, instead of a key event.
+      if (anEvent->mMessage == eKeyDown &&
+          !keyEvent->mPluginTextEventString.IsEmpty()) {
+        cocoaEvent.type = NPCocoaEventTextInput;
+        const char16_t* pluginTextEventString = keyEvent->mPluginTextEventString.get();
+        cocoaEvent.data.text.text = (NPNSString*)
+          ::CFStringCreateWithCharacters(NULL,
+                                         reinterpret_cast<const UniChar*>(pluginTextEventString),
+                                         keyEvent->mPluginTextEventString.Length());
+      } else {
+        cocoaEvent.data.key.keyCode = keyEvent->mNativeKeyCode;
+        cocoaEvent.data.key.isARepeat = keyEvent->mIsRepeat;
+        cocoaEvent.data.key.modifierFlags = keyEvent->mNativeModifierFlags;
+        const char16_t* nativeChars = keyEvent->mNativeCharacters.get();
+        cocoaEvent.data.key.characters = (NPNSString*)
+          ::CFStringCreateWithCharacters(NULL,
+                                         reinterpret_cast<const UniChar*>(nativeChars),
+                                         keyEvent->mNativeCharacters.Length());
+        const char16_t* nativeCharsIgnoringModifiers = keyEvent->mNativeCharactersIgnoringModifiers.get();
+        cocoaEvent.data.key.charactersIgnoringModifiers = (NPNSString*)
+          ::CFStringCreateWithCharacters(NULL,
+                                         reinterpret_cast<const UniChar*>(nativeCharsIgnoringModifiers),
+                                         keyEvent->mNativeCharactersIgnoringModifiers.Length());
+      }
+      break;
+    }
+    case eFocus:
+    case eBlur:
+      cocoaEvent.data.focus.hasFocus = (anEvent->mMessage == eFocus);
+      break;
+    default:
+      break;
+  }
+  return cocoaEvent;
+}
+
+void nsPluginInstanceOwner::PerformDelayedBlurs()
+{
+  nsCOMPtr<nsIContent> content = do_QueryReferent(mContent);
+  nsCOMPtr<EventTarget> windowRoot = content->OwnerDoc()->GetWindow()->GetTopWindowRoot();
+  nsContentUtils::DispatchTrustedEvent(content->OwnerDoc(),
+                                       windowRoot,
+                                       NS_LITERAL_STRING("MozPerformDelayedBlur"),
+                                       false, false, nullptr);
+}
+
+#endif
+
 nsEventStatus nsPluginInstanceOwner::ProcessEvent(const WidgetGUIEvent& anEvent)
 {
   nsEventStatus rv = nsEventStatus_eIgnore;
@@ -1408,6 +2041,85 @@ nsEventStatus nsPluginInstanceOwner::ProcessEvent(const WidgetGUIEvent& anEvent)
     return nsEventStatus_eIgnore;
   }
 
+#ifdef XP_MACOSX
+  NPEventModel eventModel = GetEventModel();
+  if (eventModel != NPEventModelCocoa) {
+    return nsEventStatus_eIgnore;
+  }
+
+  // In the Cocoa event model, focus is per-window. Don't tell a plugin it lost
+  // focus unless it lost focus within the window. For example, ignore a blur
+  // event if it's coming due to the plugin's window deactivating.
+  nsCOMPtr<nsIContent> content = do_QueryReferent(mContent);
+  if (anEvent.mMessage == eBlur && ContentIsFocusedWithinWindow(content)) {
+    mShouldBlurOnActivate = true;
+    return nsEventStatus_eIgnore;
+  }
+
+  // Also, don't tell the plugin it gained focus again after we've already given
+  // it focus. This might happen if it has focus, its window is blurred, then the
+  // window is made active again. The plugin never lost in-window focus, so it
+  // shouldn't get a focus event again.
+  if (anEvent.mMessage == eFocus && mLastContentFocused == true) {
+    mShouldBlurOnActivate = false;
+    return nsEventStatus_eIgnore;
+  }
+
+  // Now, if we're going to send a focus event, update mLastContentFocused and
+  // tell any plugins in our window that we have taken focus, so they should
+  // perform any delayed blurs.
+  if (anEvent.mMessage == eFocus || anEvent.mMessage == eBlur) {
+    mLastContentFocused = (anEvent.mMessage == eFocus);
+    mShouldBlurOnActivate = false;
+    PerformDelayedBlurs();
+  }
+
+  NPCocoaEvent cocoaEvent = TranslateToNPCocoaEvent(const_cast<WidgetGUIEvent*>(&anEvent), mPluginFrame);
+  if (cocoaEvent.type == (NPCocoaEventType)0) {
+    return nsEventStatus_eIgnore;
+  }
+
+  if (cocoaEvent.type == NPCocoaEventTextInput) {
+    mInstance->HandleEvent(&cocoaEvent, nullptr);
+    return nsEventStatus_eConsumeNoDefault;
+  }
+
+  int16_t response = kNPEventNotHandled;
+  mInstance->HandleEvent(&cocoaEvent,
+                         &response,
+                         NS_PLUGIN_CALL_SAFE_TO_REENTER_GECKO);
+  if ((response == kNPEventStartIME) && (cocoaEvent.type == NPCocoaEventKeyDown)) {
+    nsIWidget* widget = mPluginFrame->GetNearestWidget();
+    if (widget) {
+      const WidgetKeyboardEvent* keyEvent = anEvent.AsKeyboardEvent();
+      double screenX, screenY;
+      ConvertPoint(0.0, mPluginFrame->GetScreenRect().height,
+                   NPCoordinateSpacePlugin, &screenX, &screenY,
+                   NPCoordinateSpaceScreen);
+      nsAutoString outText;
+      if (NS_SUCCEEDED(widget->StartPluginIME(*keyEvent, screenX, screenY, outText)) &&
+          !outText.IsEmpty()) {
+        CFStringRef cfString =
+          ::CFStringCreateWithCharacters(kCFAllocatorDefault,
+                                         reinterpret_cast<const UniChar*>(outText.get()),
+                                         outText.Length());
+        NPCocoaEvent textEvent;
+        InitializeNPCocoaEvent(&textEvent);
+        textEvent.type = NPCocoaEventTextInput;
+        textEvent.data.text.text = (NPNSString*)cfString;
+        mInstance->HandleEvent(&textEvent, nullptr);
+      }
+    }
+  }
+
+  bool handled = (response == kNPEventHandled || response == kNPEventStartIME);
+  bool leftMouseButtonDown = (anEvent.mMessage == eMouseDown) &&
+                             (anEvent.AsMouseEvent()->button == WidgetMouseEvent::eLeftButton);
+  if (handled && !(leftMouseButtonDown && !mContentFocused)) {
+    rv = nsEventStatus_eConsumeNoDefault;
+  }
+#endif
+
 #ifdef XP_WIN
   // this code supports windowless plugins
   const NPEvent *pPluginEvent = static_cast<const NPEvent*>(anEvent.mPluginEvent);
@@ -1813,6 +2525,10 @@ nsPluginInstanceOwner::Destroy()
 {
   SetFrame(nullptr);
 
+#ifdef XP_MACOSX
+  RemoveFromCARefreshTimer();
+#endif
+
   nsCOMPtr<nsIContent> content = do_QueryReferent(mContent);
 
   // unregister context menu listener
@@ -1864,6 +2580,44 @@ nsPluginInstanceOwner::Destroy()
 
 // Paints are handled differently, so we just simulate an update event.
 
+#ifdef XP_MACOSX
+void nsPluginInstanceOwner::Paint(const gfxRect& aDirtyRect, CGContextRef cgContext)
+{
+  if (!mInstance || !mPluginFrame)
+    return;
+
+  gfxRect dirtyRectCopy = aDirtyRect;
+  double scaleFactor = 1.0;
+  GetContentsScaleFactor(&scaleFactor);
+  if (scaleFactor != 1.0) {
+    ::CGContextScaleCTM(cgContext, scaleFactor, scaleFactor);
+    // Convert aDirtyRect from device pixels to "display pixels"
+    // for HiDPI modes
+    dirtyRectCopy.ScaleRoundOut(1.0 / scaleFactor);
+  }
+
+  DoCocoaEventDrawRect(dirtyRectCopy, cgContext);
+}
+
+void nsPluginInstanceOwner::DoCocoaEventDrawRect(const gfxRect& aDrawRect, CGContextRef cgContext)
+{
+  if (!mInstance || !mPluginFrame)
+    return;
+
+  // The context given here is only valid during the HandleEvent call.
+  NPCocoaEvent updateEvent;
+  InitializeNPCocoaEvent(&updateEvent);
+  updateEvent.type = NPCocoaEventDrawRect;
+  updateEvent.data.draw.context = cgContext;
+  updateEvent.data.draw.x = aDrawRect.X();
+  updateEvent.data.draw.y = aDrawRect.Y();
+  updateEvent.data.draw.width = aDrawRect.Width();
+  updateEvent.data.draw.height = aDrawRect.Height();
+
+  mInstance->HandleEvent(&updateEvent, nullptr);
+}
+#endif
+
 #ifdef XP_WIN
 void nsPluginInstanceOwner::Paint(const RECT& aDirty, HDC aDC)
 {
@@ -2180,6 +2934,7 @@ NS_IMETHODIMP nsPluginInstanceOwner::CreateWidget(void)
     if (content) {
       doc = content->OwnerDoc();
       parentWidget = nsContentUtils::WidgetForDocument(doc);
+#ifndef XP_MACOSX
       // If we're running in the content process, we need a remote widget created in chrome.
       if (XRE_IsContentProcess()) {
         if (nsCOMPtr<nsPIDOMWindowOuter> window = doc->GetWindow()) {
@@ -2195,13 +2950,16 @@ NS_IMETHODIMP nsPluginInstanceOwner::CreateWidget(void)
           }
         }
       }
+#endif // XP_MACOSX
     }
 
+#ifndef XP_MACOSX
     // A failure here is terminal since we can't fall back on the non-e10s code
     // path below.
     if (!mWidget && XRE_IsContentProcess()) {
       return NS_ERROR_UNEXPECTED;
     }
+#endif // XP_MACOSX
 
     if (!mWidget) {
       // native (single process)
@@ -2264,11 +3022,136 @@ NS_IMETHODIMP nsPluginInstanceOwner::CreateWidget(void)
     }
   }
 
+#ifdef XP_MACOSX
+  if (GetDrawingModel() == NPDrawingModelCoreAnimation) {
+    AddToCARefreshTimer();
+  }
+#endif
+
   mWidgetCreationComplete = true;
 
   return NS_OK;
 }
 
+// Mac specific code to fix up the port location and clipping region
+#ifdef XP_MACOSX
+
+void nsPluginInstanceOwner::FixUpPluginWindow(int32_t inPaintState)
+{
+  if (!mPluginWindow || !mInstance || !mPluginFrame) {
+    return;
+  }
+
+  SetPluginPort();
+
+  LayoutDeviceIntSize widgetClip = mPluginFrame->GetWidgetlessClipRect().Size();
+
+  mPluginWindow->x = 0;
+  mPluginWindow->y = 0;
+
+  NPRect oldClipRect = mPluginWindow->clipRect;
+
+  // fix up the clipping region
+  mPluginWindow->clipRect.top  = 0;
+  mPluginWindow->clipRect.left = 0;
+
+  if (inPaintState == ePluginPaintDisable) {
+    mPluginWindow->clipRect.bottom = mPluginWindow->clipRect.top;
+    mPluginWindow->clipRect.right  = mPluginWindow->clipRect.left;
+  }
+  else if (inPaintState == ePluginPaintEnable)
+  {
+    mPluginWindow->clipRect.bottom = mPluginWindow->clipRect.top + widgetClip.height;
+    mPluginWindow->clipRect.right  = mPluginWindow->clipRect.left + widgetClip.width;
+  }
+
+  // if the clip rect changed, call SetWindow()
+  // (RealPlayer needs this to draw correctly)
+  if (mPluginWindow->clipRect.left    != oldClipRect.left   ||
+      mPluginWindow->clipRect.top     != oldClipRect.top    ||
+      mPluginWindow->clipRect.right   != oldClipRect.right  ||
+      mPluginWindow->clipRect.bottom  != oldClipRect.bottom)
+  {
+    if (UseAsyncRendering()) {
+      mInstance->AsyncSetWindow(mPluginWindow);
+    }
+    else {
+      mPluginWindow->CallSetWindow(mInstance);
+    }
+  }
+
+  // After the first NPP_SetWindow call we need to send an initial
+  // top-level window focus event.
+  if (!mSentInitialTopLevelWindowEvent) {
+    // Set this before calling ProcessEvent to avoid endless recursion.
+    mSentInitialTopLevelWindowEvent = true;
+
+    bool isActive = WindowIsActive();
+    SendWindowFocusChanged(isActive);
+    mLastWindowIsActive = isActive;
+  }
+}
+
+void
+nsPluginInstanceOwner::WindowFocusMayHaveChanged()
+{
+  if (!mSentInitialTopLevelWindowEvent) {
+    return;
+  }
+
+  bool isActive = WindowIsActive();
+  if (isActive != mLastWindowIsActive) {
+    SendWindowFocusChanged(isActive);
+    mLastWindowIsActive = isActive;
+  }
+}
+
+bool
+nsPluginInstanceOwner::WindowIsActive()
+{
+  if (!mPluginFrame) {
+    return false;
+  }
+
+  EventStates docState = mPluginFrame->GetContent()->OwnerDoc()->GetDocumentState();
+  return !docState.HasState(NS_DOCUMENT_STATE_WINDOW_INACTIVE);
+}
+
+void
+nsPluginInstanceOwner::SendWindowFocusChanged(bool aIsActive)
+{
+  if (!mInstance) {
+    return;
+  }
+
+  NPCocoaEvent cocoaEvent;
+  InitializeNPCocoaEvent(&cocoaEvent);
+  cocoaEvent.type = NPCocoaEventWindowFocusChanged;
+  cocoaEvent.data.focus.hasFocus = aIsActive;
+  mInstance->HandleEvent(&cocoaEvent,
+                         nullptr,
+                         NS_PLUGIN_CALL_SAFE_TO_REENTER_GECKO);
+}
+
+void
+nsPluginInstanceOwner::HidePluginWindow()
+{
+  if (!mPluginWindow || !mInstance) {
+    return;
+  }
+
+  mPluginWindow->clipRect.bottom = mPluginWindow->clipRect.top;
+  mPluginWindow->clipRect.right  = mPluginWindow->clipRect.left;
+  mWidgetVisible = false;
+  if (UseAsyncRendering()) {
+    mInstance->AsyncSetWindow(mPluginWindow);
+  } else {
+    mInstance->SetWindow(mPluginWindow);
+  }
+}
+
+#else // XP_MACOSX
+
 void nsPluginInstanceOwner::UpdateWindowPositionAndClipRect(bool aSetWindow)
 {
   if (!mPluginWindow)
@@ -2318,11 +3201,12 @@ nsPluginInstanceOwner::UpdateWindowVisibility(bool aVisible)
   mPluginWindowVisible = aVisible;
   UpdateWindowPositionAndClipRect(true);
 }
+#endif // XP_MACOSX
 
 void
 nsPluginInstanceOwner::ResolutionMayHaveChanged()
 {
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   double scaleFactor = 1.0;
   GetContentsScaleFactor(&scaleFactor);
   if (scaleFactor != mLastScaleFactor) {
@@ -2347,6 +3231,7 @@ nsPluginInstanceOwner::UpdateDocumentActiveState(bool aIsActive)
   PROFILER_LABEL_FUNC(js::ProfileEntry::Category::OTHER);
 
   mPluginDocumentActiveState = aIsActive;
+#ifndef XP_MACOSX
   UpdateWindowPositionAndClipRect(true);
 
   // We don't have a connection to PluginWidgetParent in the chrome
@@ -2358,6 +3243,7 @@ nsPluginInstanceOwner::UpdateDocumentActiveState(bool aIsActive)
     mWidget->Show(aIsActive);
     mWidget->Enable(aIsActive);
   }
+#endif // #ifndef XP_MACOSX
 }
 
 NS_IMETHODIMP
@@ -2385,10 +3271,10 @@ nsPluginInstanceOwner::GetContentsScaleFactor(double *result)
 {
   NS_ENSURE_ARG_POINTER(result);
   double scaleFactor = 1.0;
-  // On Windows, device pixels need to be translated to (and from) "display pixels"
+  // On Mac, device pixels need to be translated to (and from) "display pixels"
   // for plugins. On other platforms, plugin coordinates are always in device
   // pixels.
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   nsCOMPtr<nsIContent> content = do_QueryReferent(mContent);
   nsIPresShell* presShell = nsContentUtils::FindPresShellForDocument(content->OwnerDoc());
   if (presShell) {
diff --git a/dom/plugins/base/nsPluginInstanceOwner.h b/dom/plugins/base/nsPluginInstanceOwner.h
index ba16cf288c..2fa67c86e0 100644
--- a/dom/plugins/base/nsPluginInstanceOwner.h
+++ b/dom/plugins/base/nsPluginInstanceOwner.h
@@ -19,6 +19,11 @@
 #include "nsWeakReference.h"
 #include "gfxRect.h"
 
+#ifdef XP_MACOSX
+#include "mozilla/gfx/QuartzSupport.h"
+#include <ApplicationServices/ApplicationServices.h>
+#endif
+
 class nsIInputStream;
 class nsPluginDOMContextMenuListener;
 class nsPluginFrame;
@@ -99,6 +104,10 @@ public:
 
 #ifdef XP_WIN
   void Paint(const RECT& aDirty, HDC aDC);
+#elif defined(XP_MACOSX)
+  void Paint(const gfxRect& aDirtyRect, CGContextRef cgContext);  
+  void RenderCoreAnimation(CGContextRef aCGContext, int aWidth, int aHeight);
+  void DoCocoaEventDrawRect(const gfxRect& aDrawRect, CGContextRef cgContext);
 #elif defined(MOZ_X11)
   void Paint(gfxContext* aContext,
              const gfxRect& aFrameRect,
@@ -123,11 +132,33 @@ public:
   nsresult SetNetscapeWindowAsParent(HWND aWindowToAdopt);
 #endif
   
+#ifdef XP_MACOSX
+  enum { ePluginPaintEnable, ePluginPaintDisable };
+
+  void WindowFocusMayHaveChanged();
+
+  bool WindowIsActive();
+  void SendWindowFocusChanged(bool aIsActive);
+  NPDrawingModel GetDrawingModel();
+  bool IsRemoteDrawingCoreAnimation();
+
+  NPEventModel GetEventModel();
+  static void CARefresh(nsITimer *aTimer, void *aClosure);
+  void AddToCARefreshTimer();
+  void RemoveFromCARefreshTimer();
+  // This calls into the plugin (NPP_SetWindow) and can run script.
+  void FixUpPluginWindow(int32_t inPaintState);
+  void HidePluginWindow();
+  // Set plugin port info in the plugin (in the 'window' member of the
+  // NPWindow structure passed to the plugin by SetWindow()).
+  void SetPluginPort();
+#else // XP_MACOSX
   void UpdateWindowPositionAndClipRect(bool aSetWindow);
   void UpdateWindowVisibility(bool aVisible);
+#endif // XP_MACOSX
 
   void ResolutionMayHaveChanged();
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   nsresult ContentsScaleFactorChanged(double aContentsScaleFactor);
 #endif
 
@@ -183,7 +214,7 @@ public:
     return mPluginWindow->type == NPWindowTypeDrawable &&
     (MatchPluginName("Shockwave Flash") ||
      MatchPluginName("Test Plug-in"));
-#elif defined(MOZ_X11)
+#elif defined(MOZ_X11) || defined(XP_MACOSX)
     return true;
 #else
     return false;
@@ -280,6 +311,15 @@ private:
   nsCOMPtr<nsIWidget>         mWidget;
   RefPtr<nsPluginHost>      mPluginHost;
   
+#ifdef XP_MACOSX
+  static nsCOMPtr<nsITimer>                *sCATimer;
+  static nsTArray<nsPluginInstanceOwner*>  *sCARefreshListeners;
+  bool                                      mSentInitialTopLevelWindowEvent;
+  bool                                      mLastWindowIsActive;
+  bool                                      mLastContentFocused;
+  // True if, the next time the window is activated, we should blur ourselves.
+  bool                                      mShouldBlurOnActivate;
+#endif
   double                                    mLastScaleFactor;
   double                                    mLastCSSZoomFactor;
   // Initially, the event loop nesting level we were created on, it's updated
@@ -295,6 +335,15 @@ private:
   bool                        mPluginWindowVisible;
   bool                        mPluginDocumentActiveState;
 
+#ifdef XP_MACOSX
+  NPEventModel mEventModel;
+  // This is a hack! UseAsyncRendering() can incorrectly return false
+  // when we don't have an object frame (possible as of bug 90268).
+  // We hack around this by always returning true if we've ever
+  // returned true.
+  bool mUseAsyncRendering;
+#endif
+  
   // pointer to wrapper for nsIDOMContextMenuListener
   RefPtr<nsPluginDOMContextMenuListener> mCXMenuListener;
   
@@ -308,6 +357,16 @@ private:
   void CallDefaultProc(const mozilla::WidgetGUIEvent* aEvent);
 #endif
 
+#ifdef XP_MACOSX
+  static NPBool ConvertPointPuppet(PuppetWidget *widget, nsPluginFrame* pluginFrame,
+                            double sourceX, double sourceY, NPCoordinateSpace sourceSpace,
+                            double *destX, double *destY, NPCoordinateSpace destSpace);
+  static NPBool ConvertPointNoPuppet(nsIWidget *widget, nsPluginFrame* pluginFrame,
+                            double sourceX, double sourceY, NPCoordinateSpace sourceSpace,
+                            double *destX, double *destY, NPCoordinateSpace destSpace);
+  void PerformDelayedBlurs();
+#endif    // XP_MACOSX
+
   int mLastMouseDownButtonType;
 
 #ifdef MOZ_X11
diff --git a/dom/plugins/base/nsPluginNativeWindow.cpp b/dom/plugins/base/nsPluginNativeWindow.cpp
index 1c251936a5..f9baf5b813 100644
--- a/dom/plugins/base/nsPluginNativeWindow.cpp
+++ b/dom/plugins/base/nsPluginNativeWindow.cpp
@@ -27,7 +27,7 @@ nsPluginNativeWindowPLATFORM::nsPluginNativeWindowPLATFORM() : nsPluginNativeWin
   width = 0; 
   height = 0; 
   memset(&clipRect, 0, sizeof(clipRect));
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
   ws_info = nullptr;
 #endif
   type = NPWindowTypeWindow;
diff --git a/dom/plugins/base/nsPluginTags.cpp b/dom/plugins/base/nsPluginTags.cpp
index ae5ba87586..99e243a203 100644
--- a/dom/plugins/base/nsPluginTags.cpp
+++ b/dom/plugins/base/nsPluginTags.cpp
@@ -424,7 +424,7 @@ void nsPluginTag::InitMime(const char* const* aMimeTypes,
   }
 }
 
-#if !defined(XP_WIN)
+#if !defined(XP_WIN) && !defined(XP_MACOSX)
 static nsresult ConvertToUTF8(nsIUnicodeDecoder *aUnicodeDecoder,
                               nsAFlatCString& aString)
 {
@@ -448,7 +448,7 @@ static nsresult ConvertToUTF8(nsIUnicodeDecoder *aUnicodeDecoder,
 
 nsresult nsPluginTag::EnsureMembersAreUTF8()
 {
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
   return NS_OK;
 #else
   nsresult rv;
diff --git a/dom/plugins/ipc/NPEventOSX.h b/dom/plugins/ipc/NPEventOSX.h
new file mode 100644
index 0000000000..efb6845d04
--- /dev/null
+++ b/dom/plugins/ipc/NPEventOSX.h
@@ -0,0 +1,193 @@
+/* -*- Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 8 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_plugins_NPEventOSX_h
+#define mozilla_dom_plugins_NPEventOSX_h 1
+
+
+#include "npapi.h"
+
+namespace mozilla {
+
+namespace plugins {
+
+struct NPRemoteEvent {
+    NPCocoaEvent event;
+    double contentsScaleFactor;
+};
+
+} // namespace plugins
+
+} // namespace mozilla
+
+namespace IPC {
+
+template <>
+struct ParamTraits<mozilla::plugins::NPRemoteEvent>
+{
+    typedef mozilla::plugins::NPRemoteEvent paramType;
+
+    static void Write(Message* aMsg, const paramType& aParam)
+    {
+        aMsg->WriteInt(aParam.event.type);
+        aMsg->WriteUInt32(aParam.event.version);
+        switch (aParam.event.type) {
+            case NPCocoaEventMouseDown:
+            case NPCocoaEventMouseUp:
+            case NPCocoaEventMouseMoved:
+            case NPCocoaEventMouseEntered:
+            case NPCocoaEventMouseExited:
+            case NPCocoaEventMouseDragged:
+            case NPCocoaEventScrollWheel:
+                aMsg->WriteUInt32(aParam.event.data.mouse.modifierFlags);
+                aMsg->WriteDouble(aParam.event.data.mouse.pluginX);
+                aMsg->WriteDouble(aParam.event.data.mouse.pluginY);
+                aMsg->WriteInt32(aParam.event.data.mouse.buttonNumber);
+                aMsg->WriteInt32(aParam.event.data.mouse.clickCount);
+                aMsg->WriteDouble(aParam.event.data.mouse.deltaX);
+                aMsg->WriteDouble(aParam.event.data.mouse.deltaY);
+                aMsg->WriteDouble(aParam.event.data.mouse.deltaZ);
+                break;
+            case NPCocoaEventKeyDown:
+            case NPCocoaEventKeyUp:
+            case NPCocoaEventFlagsChanged:
+                aMsg->WriteUInt32(aParam.event.data.key.modifierFlags);
+                WriteParam(aMsg, aParam.event.data.key.characters);
+                WriteParam(aMsg, aParam.event.data.key.charactersIgnoringModifiers);
+                aMsg->WriteUnsignedChar(aParam.event.data.key.isARepeat);
+                aMsg->WriteUInt16(aParam.event.data.key.keyCode);
+                break;
+            case NPCocoaEventFocusChanged:
+            case NPCocoaEventWindowFocusChanged:
+                aMsg->WriteUnsignedChar(aParam.event.data.focus.hasFocus);
+                break;
+            case NPCocoaEventDrawRect:
+                // We don't write out the context pointer, it would always be
+                // nullptr and is just filled in as such on the read.
+                aMsg->WriteDouble(aParam.event.data.draw.x);
+                aMsg->WriteDouble(aParam.event.data.draw.y);
+                aMsg->WriteDouble(aParam.event.data.draw.width);
+                aMsg->WriteDouble(aParam.event.data.draw.height);
+                break;
+            case NPCocoaEventTextInput:
+                WriteParam(aMsg, aParam.event.data.text.text);
+                break;
+            default:
+                NS_NOTREACHED("Attempted to serialize unknown event type.");
+                return;
+        }
+        aMsg->WriteDouble(aParam.contentsScaleFactor);
+    }
+
+    static bool Read(const Message* aMsg, PickleIterator* aIter, paramType* aResult)
+    {
+        int type = 0;
+        if (!aMsg->ReadInt(aIter, &type)) {
+            return false;
+        }
+        aResult->event.type = static_cast<NPCocoaEventType>(type);
+
+        if (!aMsg->ReadUInt32(aIter, &aResult->event.version)) {
+            return false;
+        }
+
+        switch (aResult->event.type) {
+            case NPCocoaEventMouseDown:
+            case NPCocoaEventMouseUp:
+            case NPCocoaEventMouseMoved:
+            case NPCocoaEventMouseEntered:
+            case NPCocoaEventMouseExited:
+            case NPCocoaEventMouseDragged:
+            case NPCocoaEventScrollWheel:
+                if (!aMsg->ReadUInt32(aIter, &aResult->event.data.mouse.modifierFlags)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.mouse.pluginX)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.mouse.pluginY)) {
+                    return false;
+                }
+                if (!aMsg->ReadInt32(aIter, &aResult->event.data.mouse.buttonNumber)) {
+                    return false;
+                }
+                if (!aMsg->ReadInt32(aIter, &aResult->event.data.mouse.clickCount)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.mouse.deltaX)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.mouse.deltaY)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.mouse.deltaZ)) {
+                    return false;
+                }
+                break;
+            case NPCocoaEventKeyDown:
+            case NPCocoaEventKeyUp:
+            case NPCocoaEventFlagsChanged:
+                if (!aMsg->ReadUInt32(aIter, &aResult->event.data.key.modifierFlags)) {
+                    return false;
+                }
+                if (!ReadParam(aMsg, aIter, &aResult->event.data.key.characters)) {
+                    return false;
+                }
+                if (!ReadParam(aMsg, aIter, &aResult->event.data.key.charactersIgnoringModifiers)) {
+                    return false;
+                }
+                if (!aMsg->ReadUnsignedChar(aIter, &aResult->event.data.key.isARepeat)) {
+                    return false;
+                }
+                if (!aMsg->ReadUInt16(aIter, &aResult->event.data.key.keyCode)) {
+                    return false;
+                }
+                break;
+            case NPCocoaEventFocusChanged:
+            case NPCocoaEventWindowFocusChanged:
+                if (!aMsg->ReadUnsignedChar(aIter, &aResult->event.data.focus.hasFocus)) {
+                    return false;
+                }
+                break;
+            case NPCocoaEventDrawRect:
+                aResult->event.data.draw.context = nullptr;
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.draw.x)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.draw.y)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.draw.width)) {
+                    return false;
+                }
+                if (!aMsg->ReadDouble(aIter, &aResult->event.data.draw.height)) {
+                    return false;
+                }
+                break;
+            case NPCocoaEventTextInput:
+                if (!ReadParam(aMsg, aIter, &aResult->event.data.text.text)) {
+                    return false;
+                }
+                break;
+            default:
+                NS_NOTREACHED("Attempted to de-serialize unknown event type.");
+                return false;
+        }
+        if (!aMsg->ReadDouble(aIter, &aResult->contentsScaleFactor)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    static void Log(const paramType& aParam, std::wstring* aLog)
+    {
+        aLog->append(L"(NPCocoaEvent)");
+    }
+};
+
+} // namespace IPC
+
+#endif // ifndef mozilla_dom_plugins_NPEventOSX_h
diff --git a/dom/plugins/ipc/PluginInstanceChild.cpp b/dom/plugins/ipc/PluginInstanceChild.cpp
index e96ebb1473..a4f6b6b517 100644
--- a/dom/plugins/ipc/PluginInstanceChild.cpp
+++ b/dom/plugins/ipc/PluginInstanceChild.cpp
@@ -103,7 +103,11 @@ using mozilla::gfx::SharedDIB;
 const int kFlashWMUSERMessageThrottleDelayMs = 5;
 
 static const TCHAR kPluginIgnoreSubclassProperty[] = TEXT("PluginIgnoreSubclassProperty");
-#endif
+
+#elif defined(XP_MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#include "PluginUtilsOSX.h"
+#endif // defined(XP_MACOSX)
 
 /**
  * We can't use gfxPlatform::CreateDrawTargetForSurface() because calling
@@ -194,7 +198,7 @@ PluginInstanceChild::PluginInstanceChild(const NPPluginFuncs* aPluginIface,
     mWindow.type = NPWindowTypeWindow;
     mData.ndata = (void*) this;
     mData.pdata = nullptr;
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     mWindow.ws_info = &mWsInfo;
     memset(&mWsInfo, 0, sizeof(mWsInfo));
 #ifdef MOZ_WIDGET_GTK
@@ -203,7 +207,7 @@ PluginInstanceChild::PluginInstanceChild(const NPPluginFuncs* aPluginIface,
 #else
     mWsInfo.display = DefaultXDisplay();
 #endif
-#endif // MOZ_X11 && XP_UNIX
+#endif // MOZ_X11 && XP_UNIX && !XP_MACOSX
 #if defined(OS_WIN)
     InitPopupMenuHook();
     if (GetQuirks() & QUIRK_UNITY_FIXUP_MOUSE_CAPTURE) {
@@ -270,6 +274,23 @@ PluginInstanceChild::DoNPP_New()
 
     Initialize();
 
+#if defined(XP_MACOSX) && defined(__i386__)
+    // If an i386 Mac OS X plugin has selected the Carbon event model then
+    // we have to fail. We do not support putting Carbon event model plugins
+    // out of process. Note that Carbon is the default model so out of process
+    // plugins need to actively negotiate something else in order to work
+    // out of process.
+    if (EventModel() == NPEventModelCarbon) {
+      // Send notification that a plugin tried to negotiate Carbon NPAPI so that
+      // users can be notified that restarting the browser in i386 mode may allow
+      // them to use the plugin.
+      SendNegotiatedCarbon();
+
+      // Fail to instantiate.
+      rv = NPERR_MODULE_LOAD_FAILED_ERROR;
+    }
+#endif
+
     return rv;
 }
 
@@ -477,12 +498,58 @@ PluginInstanceChild::NPN_GetValue(NPNVariable aVar,
     }
 #endif
 
-#if defined(XP_WIN)
+#ifdef XP_MACOSX
+   case NPNVsupportsCoreGraphicsBool: {
+        *((NPBool*)aValue) = true;
+        return NPERR_NO_ERROR;
+    }
+
+    case NPNVsupportsCoreAnimationBool: {
+        *((NPBool*)aValue) = true;
+        return NPERR_NO_ERROR;
+    }
+
+    case NPNVsupportsInvalidatingCoreAnimationBool: {
+        *((NPBool*)aValue) = true;
+        return NPERR_NO_ERROR;
+    }
+
+    case NPNVsupportsCompositingCoreAnimationPluginsBool: {
+        *((NPBool*)aValue) = true;
+        return NPERR_NO_ERROR;
+    }
+
+    case NPNVsupportsCocoaBool: {
+        *((NPBool*)aValue) = true;
+        return NPERR_NO_ERROR;
+    }
+
+#ifndef NP_NO_CARBON
+    case NPNVsupportsCarbonBool: {
+      *((NPBool*)aValue) = false;
+      return NPERR_NO_ERROR;
+    }
+#endif
+
+    case NPNVsupportsUpdatedCocoaTextInputBool: {
+      *static_cast<NPBool*>(aValue) = true;
+      return NPERR_NO_ERROR;
+    }
+
+#ifndef NP_NO_QUICKDRAW
+    case NPNVsupportsQuickDrawBool: {
+        *((NPBool*)aValue) = false;
+        return NPERR_NO_ERROR;
+    }
+#endif /* NP_NO_QUICKDRAW */
+#endif /* XP_MACOSX */
+
+#if defined(XP_MACOSX) || defined(XP_WIN)
     case NPNVcontentsScaleFactor: {
         *static_cast<double*>(aValue) = mContentsScaleFactor;
         return NPERR_NO_ERROR;
     }
-#endif /* defined(XP_WIN) */
+#endif /* defined(XP_MACOSX) || defined(XP_WIN) */
 
     case NPNVCSSZoomFactor: {
         *static_cast<double*>(aValue) = mCSSZoomFactor;
@@ -587,12 +654,36 @@ PluginInstanceChild::NPN_SetValue(NPPVariable aVar, void* aValue)
 
         mDrawingModel = drawingModel;
 
+#ifdef XP_MACOSX
+        if (drawingModel == NPDrawingModelCoreAnimation) {
+            mCARefreshTimer = ScheduleTimer(DEFAULT_REFRESH_MS, true, CAUpdate);
+        }
+#endif
+
         PLUGIN_LOG_DEBUG(("  Plugin requested drawing model id  #%i\n",
             mDrawingModel));
 
         return rv;
     }
 
+#ifdef XP_MACOSX
+    case NPPVpluginEventModel: {
+        NPError rv;
+        int eventModel = (int16_t) (intptr_t) aValue;
+
+        if (!CallNPN_SetValue_NPPVpluginEventModel(eventModel, &rv))
+            return NPERR_GENERIC_ERROR;
+#if defined(__i386__)
+        mEventModel = static_cast<NPEventModel>(eventModel);
+#endif
+
+        PLUGIN_LOG_DEBUG(("  Plugin requested event model id # %i\n",
+            eventModel));
+
+        return rv;
+    }
+#endif
+
     case NPPVpluginIsPlayingAudio: {
         NPError rv = NPERR_GENERIC_ERROR;
         if (!CallNPN_SetValue_NPPVpluginIsPlayingAudio((NPBool)(intptr_t)aValue, &rv)) {
@@ -816,10 +907,21 @@ PluginInstanceChild::AnswerNPP_HandleEvent(const NPRemoteEvent& event,
                           event.event.xgraphicsexpose.drawable));
 #endif
 
+#ifdef XP_MACOSX
+    // Mac OS X does not define an NPEvent structure. It defines more specific types.
+    NPCocoaEvent evcopy = event.event;
+
+    // Make sure we reset mCurrentEvent in case of an exception
+    AutoRestore<const NPCocoaEvent*> savePreviousEvent(mCurrentEvent);
+
+    // Track the current event for NPN_PopUpContextMenu.
+    mCurrentEvent = &event.event;
+#else
     // Make a copy since we may modify values.
     NPEvent evcopy = event.event;
+#endif
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     // event.contentsScaleFactor <= 0 is a signal we shouldn't use it,
     // for example when AnswerNPP_HandleEvent() is called from elsewhere
     // in the child process (not via rpc code from the parent process).
@@ -845,6 +947,18 @@ PluginInstanceChild::AnswerNPP_HandleEvent(const NPRemoteEvent& event,
     else
         *handled = mPluginIface->event(&mData, reinterpret_cast<void*>(&evcopy));
 
+#ifdef XP_MACOSX
+    // Release any reference counted objects created in the child process.
+    if (evcopy.type == NPCocoaEventKeyDown ||
+        evcopy.type == NPCocoaEventKeyUp) {
+      ::CFRelease((CFStringRef)evcopy.data.key.characters);
+      ::CFRelease((CFStringRef)evcopy.data.key.charactersIgnoringModifiers);
+    }
+    else if (evcopy.type == NPCocoaEventTextInput) {
+      ::CFRelease((CFStringRef)evcopy.data.text.text);
+    }
+#endif
+
 #ifdef MOZ_X11
     if (GraphicsExpose == event.event.type) {
         // Make sure the X server completes the drawing before the parent
@@ -861,6 +975,73 @@ PluginInstanceChild::AnswerNPP_HandleEvent(const NPRemoteEvent& event,
     return true;
 }
 
+#ifdef XP_MACOSX
+
+bool
+PluginInstanceChild::AnswerNPP_HandleEvent_Shmem(const NPRemoteEvent& event,
+                                                 Shmem&& mem,
+                                                 int16_t* handled,
+                                                 Shmem* rtnmem)
+{
+    PLUGIN_LOG_DEBUG_FUNCTION;
+    AssertPluginThread();
+    AutoStackHelper guard(this);
+
+    PaintTracker pt;
+
+    NPCocoaEvent evcopy = event.event;
+    mContentsScaleFactor = event.contentsScaleFactor;
+
+    if (evcopy.type == NPCocoaEventDrawRect) {
+        int scaleFactor = ceil(mContentsScaleFactor);
+        if (!mShColorSpace) {
+            mShColorSpace = CreateSystemColorSpace();
+            if (!mShColorSpace) {
+                PLUGIN_LOG_DEBUG(("Could not allocate ColorSpace."));
+                *handled = false;
+                *rtnmem = mem;
+                return true;
+            } 
+        }
+        if (!mShContext) {
+            void* cgContextByte = mem.get<char>();
+            mShContext = ::CGBitmapContextCreate(cgContextByte, 
+                              mWindow.width * scaleFactor,
+                              mWindow.height * scaleFactor, 8, 
+                              mWindow.width * 4 * scaleFactor, mShColorSpace, 
+                              kCGImageAlphaPremultipliedFirst |
+                              kCGBitmapByteOrder32Host);
+    
+            if (!mShContext) {
+                PLUGIN_LOG_DEBUG(("Could not allocate CGBitmapContext."));
+                *handled = false;
+                *rtnmem = mem;
+                return true;
+            }
+        }
+        CGRect clearRect = ::CGRectMake(0, 0, mWindow.width, mWindow.height);
+        ::CGContextClearRect(mShContext, clearRect);
+        evcopy.data.draw.context = mShContext; 
+    } else {
+        PLUGIN_LOG_DEBUG(("Invalid event type for AnswerNNP_HandleEvent_Shmem."));
+        *handled = false;
+        *rtnmem = mem;
+        return true;
+    } 
+
+    if (!mPluginIface->event) {
+        *handled = false;
+    } else {
+        ::CGContextSaveGState(evcopy.data.draw.context);
+        *handled = mPluginIface->event(&mData, reinterpret_cast<void*>(&evcopy));
+        ::CGContextRestoreGState(evcopy.data.draw.context);
+    }
+
+    *rtnmem = mem;
+    return true;
+}
+
+#else
 bool
 PluginInstanceChild::AnswerNPP_HandleEvent_Shmem(const NPRemoteEvent& event,
                                                  Shmem&& mem,
@@ -871,15 +1052,110 @@ PluginInstanceChild::AnswerNPP_HandleEvent_Shmem(const NPRemoteEvent& event,
     *rtnmem = mem;
     return true;
 }
+#endif
+
+#ifdef XP_MACOSX
+
+void CallCGDraw(CGContextRef ref, void* aPluginInstance, nsIntRect aUpdateRect) {
+  PluginInstanceChild* pluginInstance = (PluginInstanceChild*)aPluginInstance;
+
+  pluginInstance->CGDraw(ref, aUpdateRect);
+}
+
+bool
+PluginInstanceChild::CGDraw(CGContextRef ref, nsIntRect aUpdateRect) {
+
+  NPCocoaEvent drawEvent;
+  drawEvent.type = NPCocoaEventDrawRect;
+  drawEvent.version = 0;
+  drawEvent.data.draw.x = aUpdateRect.x;
+  drawEvent.data.draw.y = aUpdateRect.y;
+  drawEvent.data.draw.width = aUpdateRect.width;
+  drawEvent.data.draw.height = aUpdateRect.height;
+  drawEvent.data.draw.context = ref;
+
+  NPRemoteEvent remoteDrawEvent = {drawEvent};
+  // Signal to AnswerNPP_HandleEvent() not to use this value
+  remoteDrawEvent.contentsScaleFactor = -1.0;
+
+  int16_t handled;
+  AnswerNPP_HandleEvent(remoteDrawEvent, &handled);
+  return handled == true;
+}
 
 bool
 PluginInstanceChild::AnswerNPP_HandleEvent_IOSurface(const NPRemoteEvent& event,
                                                      const uint32_t &surfaceid,
                                                      int16_t* handled)
 {
+    PLUGIN_LOG_DEBUG_FUNCTION;
+    AssertPluginThread();
+    AutoStackHelper guard(this);
+
+    PaintTracker pt;
+
+    NPCocoaEvent evcopy = event.event;
+    mContentsScaleFactor = event.contentsScaleFactor;
+    RefPtr<MacIOSurface> surf = MacIOSurface::LookupSurface(surfaceid,
+                                                            mContentsScaleFactor);
+    if (!surf) {
+        NS_ERROR("Invalid IOSurface.");
+        *handled = false;
+        return false;
+    }
+
+    if (!mCARenderer) {
+      mCARenderer = new nsCARenderer();
+    }
+
+    if (evcopy.type == NPCocoaEventDrawRect) {
+        mCARenderer->AttachIOSurface(surf);
+        if (!mCARenderer->isInit()) {
+            void *caLayer = nullptr;
+            NPError result = mPluginIface->getvalue(GetNPP(), 
+                                     NPPVpluginCoreAnimationLayer,
+                                     &caLayer);
+            
+            if (result != NPERR_NO_ERROR || !caLayer) {
+                PLUGIN_LOG_DEBUG(("Plugin requested CoreAnimation but did not "
+                                  "provide CALayer."));
+                *handled = false;
+                return false;
+            }
+
+            mCARenderer->SetupRenderer(caLayer, mWindow.width, mWindow.height,
+                            mContentsScaleFactor,
+                            GetQuirks() & QUIRK_ALLOW_OFFLINE_RENDERER ?
+                            ALLOW_OFFLINE_RENDERER : DISALLOW_OFFLINE_RENDERER);
+
+            // Flash needs to have the window set again after this step
+            if (mPluginIface->setwindow)
+                (void) mPluginIface->setwindow(&mData, &mWindow);
+        }
+    } else {
+        PLUGIN_LOG_DEBUG(("Invalid event type for "
+                          "AnswerNNP_HandleEvent_IOSurface."));
+        *handled = false;
+        return false;
+    } 
+
+    mCARenderer->Render(mWindow.width, mWindow.height,
+                        mContentsScaleFactor, nullptr);
+
+    return true;
+
+}
+
+#else
+bool
+PluginInstanceChild::AnswerNPP_HandleEvent_IOSurface(const NPRemoteEvent& event,
+                                                     const uint32_t &surfaceid,
+                                                     int16_t* handled)
+{
     NS_RUNTIMEABORT("NPP_HandleEvent_IOSurface is a OSX-only message");
     return false;
 }
+#endif
 
 bool
 PluginInstanceChild::RecvWindowPosChanged(const NPRemoteEvent& event)
@@ -899,16 +1175,24 @@ PluginInstanceChild::RecvWindowPosChanged(const NPRemoteEvent& event)
 bool
 PluginInstanceChild::RecvContentsScaleFactorChanged(const double& aContentsScaleFactor)
 {
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     mContentsScaleFactor = aContentsScaleFactor;
+#if defined(XP_MACOSX)
+    if (mShContext) {
+        // Release the shared context so that it is reallocated
+        // with the new size. 
+        ::CGContextRelease(mShContext);
+        mShContext = nullptr;
+    }
+#endif
     return true;
 #else
-    NS_RUNTIMEABORT("ContentsScaleFactorChanged is a Windows-only message");
+    NS_RUNTIMEABORT("ContentsScaleFactorChanged is an Windows or OSX only message");
     return false;
 #endif
 }
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
 // Create a new window from NPWindow
 bool PluginInstanceChild::CreateWindow(const NPRemoteWindow& aWindow)
 { 
@@ -1006,7 +1290,7 @@ PluginInstanceChild::AnswerNPP_SetWindow(const NPRemoteWindow& aWindow)
     AssertPluginThread();
     AutoStackHelper guard(this);
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     NS_ASSERTION(mWsInfo.display, "We should have a valid display!");
 
     // The minimum info is sent over IPC to allow this
@@ -1123,6 +1407,26 @@ PluginInstanceChild::AnswerNPP_SetWindow(const NPRemoteWindow& aWindow)
       break;
     }
 
+#elif defined(XP_MACOSX)
+
+    mWindow.x = aWindow.x;
+    mWindow.y = aWindow.y;
+    mWindow.width = aWindow.width;
+    mWindow.height = aWindow.height;
+    mWindow.clipRect = aWindow.clipRect;
+    mWindow.type = aWindow.type;
+    mContentsScaleFactor = aWindow.contentsScaleFactor;
+
+    if (mShContext) {
+        // Release the shared context so that it is reallocated
+        // with the new size. 
+        ::CGContextRelease(mShContext);
+        mShContext = nullptr;
+    }
+
+    if (mPluginIface->setwindow)
+        (void) mPluginIface->setwindow(&mData, &mWindow);
+
 #elif defined(MOZ_WIDGET_UIKIT)
     // Don't care
 #else
@@ -3068,7 +3372,7 @@ PluginInstanceChild::DoAsyncSetWindow(const gfxSurfaceType& aSurfaceType,
     mWindow.height = aWindow.height;
     mWindow.clipRect = aWindow.clipRect;
     mWindow.type = aWindow.type;
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     mContentsScaleFactor = aWindow.contentsScaleFactor;
 #endif
 
@@ -3260,6 +3564,60 @@ PluginInstanceChild::EnsureCurrentBuffer(void)
         NS_ERROR("Cannot create helper surface");
         return false;
     }
+
+    return true;
+#elif defined(XP_MACOSX)
+
+    if (!mDoubleBufferCARenderer.HasCALayer()) {
+        void *caLayer = nullptr;
+        if (mDrawingModel == NPDrawingModelCoreGraphics) {
+            if (!mCGLayer) {
+                caLayer = mozilla::plugins::PluginUtilsOSX::GetCGLayer(CallCGDraw,
+                                                                       this,
+                                                                       mContentsScaleFactor);
+
+                if (!caLayer) {
+                    PLUGIN_LOG_DEBUG(("GetCGLayer failed."));
+                    return false;
+                }
+            }
+            mCGLayer = caLayer;
+        } else {
+            NPError result = mPluginIface->getvalue(GetNPP(),
+                                     NPPVpluginCoreAnimationLayer,
+                                     &caLayer);
+            if (result != NPERR_NO_ERROR || !caLayer) {
+                PLUGIN_LOG_DEBUG(("Plugin requested CoreAnimation but did not "
+                                  "provide CALayer."));
+                return false;
+            }
+        }
+        mDoubleBufferCARenderer.SetCALayer(caLayer);
+    }
+
+    if (mDoubleBufferCARenderer.HasFrontSurface() &&
+        (mDoubleBufferCARenderer.GetFrontSurfaceWidth() != mWindow.width ||
+         mDoubleBufferCARenderer.GetFrontSurfaceHeight() != mWindow.height ||
+         mDoubleBufferCARenderer.GetContentsScaleFactor() != mContentsScaleFactor)) {
+        mDoubleBufferCARenderer.ClearFrontSurface();
+    }
+
+    if (!mDoubleBufferCARenderer.HasFrontSurface()) {
+        bool allocSurface = mDoubleBufferCARenderer.InitFrontSurface(
+                                mWindow.width, mWindow.height, mContentsScaleFactor,
+                                GetQuirks() & QUIRK_ALLOW_OFFLINE_RENDERER ?
+                                ALLOW_OFFLINE_RENDERER : DISALLOW_OFFLINE_RENDERER);
+        if (!allocSurface) {
+            PLUGIN_LOG_DEBUG(("Fail to allocate front IOSurface"));
+            return false;
+        }
+
+        if (mPluginIface->setwindow)
+            (void) mPluginIface->setwindow(&mData, &mWindow);
+
+        nsIntRect toInvalidate(0, 0, mWindow.width, mWindow.height);
+        mAccumulatedInvalidRect.UnionRect(mAccumulatedInvalidRect, toInvalidate);
+    }
 #endif
     return true;
 }
@@ -3304,6 +3662,8 @@ PluginInstanceChild::UpdateWindowAttributes(bool aForceSetWindow)
         return;
     }
 
+#ifndef XP_MACOSX
+    // Adjusting the window isn't needed for OSX
 #ifndef XP_WIN
     // On Windows, we translate the device context, in order for the window
     // origin to be correct.
@@ -3324,6 +3684,7 @@ PluginInstanceChild::UpdateWindowAttributes(bool aForceSetWindow)
         mWindow.clipRect.right = clipRect.XMost();
         mWindow.clipRect.bottom = clipRect.YMost();
     }
+#endif // XP_MACOSX
 
 #ifdef XP_WIN
     // Windowless plugins on Windows need a WM_WINDOWPOSCHANGED event to update
@@ -4294,7 +4655,7 @@ PluginInstanceChild::Destroy()
       xt_client_xloop_destroy();
     }
 #endif
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     DeleteWindow();
 #endif
 }
diff --git a/dom/plugins/ipc/PluginInstanceChild.h b/dom/plugins/ipc/PluginInstanceChild.h
index e07431c52a..0ad6e145d7 100644
--- a/dom/plugins/ipc/PluginInstanceChild.h
+++ b/dom/plugins/ipc/PluginInstanceChild.h
@@ -206,7 +206,7 @@ protected:
     virtual bool
     RecvNPP_DidComposite() override;
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     bool CreateWindow(const NPRemoteWindow& aWindow);
     void DeleteWindow();
 #endif
@@ -456,7 +456,7 @@ private:
     PluginScriptableObjectChild* mCachedWindowActor;
     PluginScriptableObjectChild* mCachedElementActor;
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     NPSetWindowCallbackStruct mWsInfo;
 #ifdef MOZ_WIDGET_GTK
     bool mXEmbed;
@@ -520,10 +520,15 @@ private:
     bool CanPaintOnBackground();
 
     bool IsVisible() {
+#ifdef XP_MACOSX
+        return mWindow.clipRect.top != mWindow.clipRect.bottom &&
+               mWindow.clipRect.left != mWindow.clipRect.right;
+#else
         return mWindow.clipRect.top != 0 ||
             mWindow.clipRect.left != 0 ||
             mWindow.clipRect.bottom != 0 ||
             mWindow.clipRect.right != 0;
+#endif
     }
 
     // ShowPluginFrame - in general does four things:
@@ -604,6 +609,12 @@ private:
     // surface which is on ParentProcess side
     RefPtr<gfxASurface> mBackSurface;
 
+#ifdef XP_MACOSX
+    // Current IOSurface available for rendering
+    // We can't use thebes gfxASurface like other platforms.
+    PluginUtilsOSX::nsDoubleBufferCARenderer mDoubleBufferCARenderer; 
+#endif
+
     // (Not to be confused with mBackSurface).  This is a recent copy
     // of the opaque pixels under our object frame, if
     // |mIsTransparent|.  We ask the plugin render directly onto a
diff --git a/dom/plugins/ipc/PluginInstanceParent.cpp b/dom/plugins/ipc/PluginInstanceParent.cpp
index 85c95077aa..372a7a238b 100644
--- a/dom/plugins/ipc/PluginInstanceParent.cpp
+++ b/dom/plugins/ipc/PluginInstanceParent.cpp
@@ -50,6 +50,10 @@
 # include "mozilla/layers/TextureD3D11.h"
 #endif
 
+#ifdef XP_MACOSX
+#include "MacIOSurfaceImage.h"
+#endif
+
 #if defined(OS_WIN)
 #include <windowsx.h>
 #include "gfxWindowsPlatform.h"
@@ -63,7 +67,9 @@ extern const wchar_t* kFlashFullscreenClass;
 #elif defined(MOZ_WIDGET_GTK)
 #include "mozilla/dom/ContentChild.h"
 #include <gdk/gdk.h>
-#endif
+#elif defined(XP_MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#endif // defined(XP_MACOSX)
 
 using namespace mozilla;
 using namespace mozilla::plugins;
@@ -128,6 +134,11 @@ PluginInstanceParent::PluginInstanceParent(PluginModuleParent* parent,
     , mPluginWndProc(nullptr)
     , mNestedEventState(false)
 #endif // defined(XP_WIN)
+#if defined(XP_MACOSX)
+    , mShWidth(0)
+    , mShHeight(0)
+    , mShColorSpace(nullptr)
+#endif
 {
 #if defined(OS_WIN)
     if (!sPluginInstanceList) {
@@ -447,7 +458,14 @@ PluginInstanceParent::AnswerNPN_SetValue_NPPVpluginDrawingModel(
     bool allowed = false;
 
     switch (drawingModel) {
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+        case NPDrawingModelCoreAnimation:
+        case NPDrawingModelInvalidatingCoreAnimation:
+        case NPDrawingModelOpenGL:
+        case NPDrawingModelCoreGraphics:
+            allowed = true;
+            break;
+#elif defined(XP_WIN)
         case NPDrawingModelSyncWin:
             allowed = true;
             break;
@@ -476,6 +494,16 @@ PluginInstanceParent::AnswerNPN_SetValue_NPPVpluginDrawingModel(
 
     int requestModel = drawingModel;
 
+#ifdef XP_MACOSX
+    if (drawingModel == NPDrawingModelCoreAnimation ||
+        drawingModel == NPDrawingModelInvalidatingCoreAnimation) {
+        // We need to request CoreGraphics otherwise
+        // the nsPluginFrame will try to draw a CALayer
+        // that can not be shared across process.
+        requestModel = NPDrawingModelCoreGraphics;
+    }
+#endif
+
     *result = mNPNIface->setvalue(mNPP, NPPVpluginDrawingModel,
                                   (void*)(intptr_t)requestModel);
 
@@ -486,8 +514,14 @@ bool
 PluginInstanceParent::AnswerNPN_SetValue_NPPVpluginEventModel(
     const int& eventModel, NPError* result)
 {
+#ifdef XP_MACOSX
+    *result = mNPNIface->setvalue(mNPP, NPPVpluginEventModel,
+                                  (void*)(intptr_t)eventModel);
+    return true;
+#else
     *result = NPERR_GENERIC_ERROR;
     return true;
+#endif
 }
 
 bool
@@ -841,6 +875,35 @@ PluginInstanceParent::RecvShow(const NPRect& updatedRect,
         }
         surface = gfxSharedImageSurface::Open(newSurface.get_Shmem());
     }
+#ifdef XP_MACOSX
+    else if (newSurface.type() == SurfaceDescriptor::TIOSurfaceDescriptor) {
+        IOSurfaceDescriptor iodesc = newSurface.get_IOSurfaceDescriptor();
+
+        RefPtr<MacIOSurface> newIOSurface =
+          MacIOSurface::LookupSurface(iodesc.surfaceId(),
+                                      iodesc.contentsScaleFactor());
+
+        if (!newIOSurface) {
+            NS_WARNING("Got bad IOSurfaceDescriptor in RecvShow");
+            return false;
+        }
+
+        if (mFrontIOSurface)
+            *prevSurface = IOSurfaceDescriptor(mFrontIOSurface->GetIOSurfaceID(),
+                                               mFrontIOSurface->GetContentsScaleFactor());
+        else
+            *prevSurface = null_t();
+
+        mFrontIOSurface = newIOSurface;
+
+        RecvNPN_InvalidateRect(updatedRect);
+
+        PLUGIN_LOG_DEBUG(("   (RecvShow invalidated for surface %p)",
+                          mFrontSurface.get()));
+
+        return true;
+    }
+#endif
 #ifdef MOZ_X11
     else if (newSurface.type() == SurfaceDescriptor::TSurfaceDescriptorX11) {
         surface = newSurface.get_SurfaceDescriptorX11().OpenForeign();
@@ -922,7 +985,7 @@ PluginInstanceParent::AsyncSetWindow(NPWindow* aWindow)
     window.height = aWindow->height;
     window.clipRect = aWindow->clipRect;
     window.type = aWindow->type;
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     double scaleFactor = 1.0;
     mNPNIface->getvalue(mNPP, NPNVcontentsScaleFactor, &scaleFactor);
     window.contentsScaleFactor = scaleFactor;
@@ -952,7 +1015,19 @@ PluginInstanceParent::GetImageContainer(ImageContainer** aContainer)
         return NS_OK;
     }
 
+#ifdef XP_MACOSX
+    MacIOSurface* ioSurface = nullptr;
+
+    if (mFrontIOSurface) {
+      ioSurface = mFrontIOSurface;
+    } else if (mIOSurface) {
+      ioSurface = mIOSurface;
+    }
+
+    if (!mFrontSurface && !ioSurface)
+#else
     if (!mFrontSurface)
+#endif
         return NS_ERROR_NOT_AVAILABLE;
 
     ImageContainer *container = GetImageContainer();
@@ -961,6 +1036,17 @@ PluginInstanceParent::GetImageContainer(ImageContainer** aContainer)
         return NS_ERROR_FAILURE;
     }
 
+#ifdef XP_MACOSX
+    if (ioSurface) {
+        RefPtr<Image> image = new MacIOSurfaceImage(ioSurface);
+        container->SetCurrentImageInTransaction(image);
+
+        NS_IF_ADDREF(container);
+        *aContainer = container;
+        return NS_OK;
+    }
+#endif
+
     NS_IF_ADDREF(container);
     *aContainer = container;
     return NS_OK;
@@ -983,6 +1069,16 @@ PluginInstanceParent::GetImageSize(nsIntSize* aSize)
         return NS_OK;
     }
 
+#ifdef XP_MACOSX
+    if (mFrontIOSurface) {
+        *aSize = nsIntSize(mFrontIOSurface->GetWidth(), mFrontIOSurface->GetHeight());
+        return NS_OK;
+    } else if (mIOSurface) {
+        *aSize = nsIntSize(mIOSurface->GetWidth(), mIOSurface->GetHeight());
+        return NS_OK;
+    }
+#endif
+
     return NS_ERROR_NOT_AVAILABLE;
 }
 
@@ -995,14 +1091,23 @@ PluginInstanceParent::DidComposite()
     Unused << SendNPP_DidComposite();
 }
 
-#if defined(XP_WIN)
+#ifdef XP_MACOSX
+nsresult
+PluginInstanceParent::IsRemoteDrawingCoreAnimation(bool *aDrawing)
+{
+    *aDrawing = (NPDrawingModelCoreAnimation == (NPDrawingModel)mDrawingModel ||
+                 NPDrawingModelInvalidatingCoreAnimation == (NPDrawingModel)mDrawingModel);
+    return NS_OK;
+}
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
 nsresult
 PluginInstanceParent::ContentsScaleFactorChanged(double aContentsScaleFactor)
 {
     bool rv = SendContentsScaleFactorChanged(aContentsScaleFactor);
     return rv ? NS_OK : NS_ERROR_FAILURE;
 }
-#endif // #ifdef XP_WIN
+#endif // #ifdef XP_MACOSX
 
 nsresult
 PluginInstanceParent::SetBackgroundUnknown()
@@ -1254,14 +1359,40 @@ PluginInstanceParent::NPP_SetWindow(const NPWindow* aWindow)
     window.type = aWindow->type;
 #endif
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     double floatScaleFactor = 1.0;
     mNPNIface->getvalue(mNPP, NPNVcontentsScaleFactor, &floatScaleFactor);
     int scaleFactor = ceil(floatScaleFactor);
     window.contentsScaleFactor = floatScaleFactor;
 #endif
+#if defined(XP_MACOSX)
+    if (mShWidth != window.width * scaleFactor || mShHeight != window.height * scaleFactor) {
+        if (mDrawingModel == NPDrawingModelCoreAnimation ||
+            mDrawingModel == NPDrawingModelInvalidatingCoreAnimation) {
+            mIOSurface = MacIOSurface::CreateIOSurface(window.width, window.height,
+                                                       floatScaleFactor);
+        } else if (uint32_t(mShWidth * mShHeight) !=
+                   window.width * scaleFactor * window.height * scaleFactor) {
+            if (mShWidth != 0 && mShHeight != 0) {
+                DeallocShmem(mShSurface);
+                mShWidth = 0;
+                mShHeight = 0;
+            }
+
+            if (window.width != 0 && window.height != 0) {
+                if (!AllocShmem(window.width * scaleFactor * window.height*4 * scaleFactor,
+                                SharedMemory::TYPE_BASIC, &mShSurface)) {
+                    PLUGIN_LOG_DEBUG(("Shared memory could not be allocated."));
+                    return NPERR_GENERIC_ERROR;
+                }
+            }
+        }
+        mShWidth = window.width * scaleFactor;
+        mShHeight = window.height * scaleFactor;
+    }
+#endif
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     const NPSetWindowCallbackStruct* ws_info =
       static_cast<NPSetWindowCallbackStruct*>(aWindow->ws_info);
     window.visualID = ws_info->visual ? ws_info->visual->visualid : 0;
@@ -1421,10 +1552,14 @@ PluginInstanceParent::NPP_HandleEvent(void* event)
 {
     PLUGIN_LOG_DEBUG_FUNCTION;
 
+#if defined(XP_MACOSX)
+    NPCocoaEvent* npevent = reinterpret_cast<NPCocoaEvent*>(event);
+#else
     NPEvent* npevent = reinterpret_cast<NPEvent*>(event);
+#endif
     NPRemoteEvent npremoteevent;
     npremoteevent.event = *npevent;
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     double scaleFactor = 1.0;
     mNPNIface->getvalue(mNPP, NPNVcontentsScaleFactor, &scaleFactor);
     npremoteevent.contentsScaleFactor = scaleFactor;
@@ -1514,6 +1649,111 @@ PluginInstanceParent::NPP_HandleEvent(void* event)
     }
 #endif
 
+#ifdef XP_MACOSX
+    if (npevent->type == NPCocoaEventDrawRect) {
+        if (mDrawingModel == NPDrawingModelCoreAnimation ||
+            mDrawingModel == NPDrawingModelInvalidatingCoreAnimation) {
+            if (!mIOSurface) {
+                NS_ERROR("No IOSurface allocated.");
+                return false;
+            }
+            if (!CallNPP_HandleEvent_IOSurface(npremoteevent,
+                                               mIOSurface->GetIOSurfaceID(),
+                                               &handled))
+                return false; // no good way to handle errors here...
+
+            CGContextRef cgContext = npevent->data.draw.context;
+            if (!mShColorSpace) {
+                mShColorSpace = CreateSystemColorSpace();
+            }
+            if (!mShColorSpace) {
+                PLUGIN_LOG_DEBUG(("Could not allocate ColorSpace."));
+                return false;
+            }
+            if (cgContext) {
+                nsCARenderer::DrawSurfaceToCGContext(cgContext, mIOSurface,
+                                                     mShColorSpace,
+                                                     npevent->data.draw.x,
+                                                     npevent->data.draw.y,
+                                                     npevent->data.draw.width,
+                                                     npevent->data.draw.height);
+            }
+            return true;
+        } else if (mFrontIOSurface) {
+            CGContextRef cgContext = npevent->data.draw.context;
+            if (!mShColorSpace) {
+                mShColorSpace = CreateSystemColorSpace();
+            }
+            if (!mShColorSpace) {
+                PLUGIN_LOG_DEBUG(("Could not allocate ColorSpace."));
+                return false;
+            }
+            if (cgContext) {
+                nsCARenderer::DrawSurfaceToCGContext(cgContext, mFrontIOSurface,
+                                                     mShColorSpace,
+                                                     npevent->data.draw.x,
+                                                     npevent->data.draw.y,
+                                                     npevent->data.draw.width,
+                                                     npevent->data.draw.height);
+            }
+            return true;
+        } else {
+            if (mShWidth == 0 && mShHeight == 0) {
+                PLUGIN_LOG_DEBUG(("NPCocoaEventDrawRect on window of size 0."));
+                return false;
+            }
+            if (!mShSurface.IsReadable()) {
+                PLUGIN_LOG_DEBUG(("Shmem is not readable."));
+                return false;
+            }
+
+            if (!CallNPP_HandleEvent_Shmem(npremoteevent, mShSurface,
+                                           &handled, &mShSurface))
+                return false; // no good way to handle errors here...
+
+            if (!mShSurface.IsReadable()) {
+                PLUGIN_LOG_DEBUG(("Shmem not returned. Either the plugin crashed "
+                                  "or we have a bug."));
+                return false;
+            }
+
+            char* shContextByte = mShSurface.get<char>();
+
+            if (!mShColorSpace) {
+                mShColorSpace = CreateSystemColorSpace();
+            }
+            if (!mShColorSpace) {
+                PLUGIN_LOG_DEBUG(("Could not allocate ColorSpace."));
+                return false;
+            }
+            CGContextRef shContext = ::CGBitmapContextCreate(shContextByte,
+                                    mShWidth, mShHeight, 8,
+                                    mShWidth*4, mShColorSpace,
+                                    kCGImageAlphaPremultipliedFirst |
+                                    kCGBitmapByteOrder32Host);
+            if (!shContext) {
+                PLUGIN_LOG_DEBUG(("Could not allocate CGBitmapContext."));
+                return false;
+            }
+
+            CGImageRef shImage = ::CGBitmapContextCreateImage(shContext);
+            if (shImage) {
+                CGContextRef cgContext = npevent->data.draw.context;
+
+                ::CGContextDrawImage(cgContext,
+                                     CGRectMake(0,0,mShWidth,mShHeight),
+                                     shImage);
+                ::CGImageRelease(shImage);
+            } else {
+                ::CGContextRelease(shContext);
+                return false;
+            }
+            ::CGContextRelease(shContext);
+            return true;
+        }
+    }
+#endif
+
     if (!CallNPP_HandleEvent(npremoteevent, &handled))
         return 0; // no good way to handle errors here...
 
diff --git a/dom/plugins/ipc/PluginInstanceParent.h b/dom/plugins/ipc/PluginInstanceParent.h
index 7c9febb242..cb85378db6 100644
--- a/dom/plugins/ipc/PluginInstanceParent.h
+++ b/dom/plugins/ipc/PluginInstanceParent.h
@@ -321,7 +321,10 @@ public:
     nsresult AsyncSetWindow(NPWindow* window);
     nsresult GetImageContainer(mozilla::layers::ImageContainer** aContainer);
     nsresult GetImageSize(nsIntSize* aSize);
-#if defined(XP_WIN)
+#ifdef XP_MACOSX
+    nsresult IsRemoteDrawingCoreAnimation(bool *aDrawing);
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
     nsresult ContentsScaleFactorChanged(double aContentsScaleFactor);
 #endif
     nsresult SetBackgroundUnknown();
diff --git a/dom/plugins/ipc/PluginInterposeOSX.h b/dom/plugins/ipc/PluginInterposeOSX.h
new file mode 100644
index 0000000000..2a742b8aa2
--- /dev/null
+++ b/dom/plugins/ipc/PluginInterposeOSX.h
@@ -0,0 +1,137 @@
+// vim:set ts=2 sts=2 sw=2 et cin:
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef DOM_PLUGINS_IPC_PLUGININTERPOSEOSX_H
+#define DOM_PLUGINS_IPC_PLUGININTERPOSEOSX_H
+
+#include "base/basictypes.h"
+#include "nsPoint.h"
+#include "npapi.h"
+
+// Make this includable from non-Objective-C code.
+#ifndef __OBJC__
+class NSCursor;
+#else
+#import <Cocoa/Cocoa.h>
+#endif
+
+// The header file QuickdrawAPI.h is missing on OS X 10.7 and up (though the
+// QuickDraw APIs defined in it are still present) -- so we need to supply the
+// relevant parts of its contents here.  It's likely that Apple will eventually
+// remove the APIs themselves (probably in OS X 10.8), so we need to make them
+// weak imports, and test for their presence before using them.
+#if !defined(__QUICKDRAWAPI__)
+
+typedef short Bits16[16];
+struct Cursor {
+  Bits16  data;
+  Bits16  mask;
+  Point   hotSpot;
+};
+typedef struct Cursor Cursor;
+
+#endif /* __QUICKDRAWAPI__ */
+
+namespace mac_plugin_interposing {
+
+// Class used to serialize NSCursor objects over IPC between processes.
+class NSCursorInfo {
+public:
+  enum Type {
+    TypeCustom,
+    TypeArrow,
+    TypeClosedHand,
+    TypeContextualMenu,   // Only supported on OS X 10.6 and up
+    TypeCrosshair,
+    TypeDisappearingItem,
+    TypeDragCopy,         // Only supported on OS X 10.6 and up
+    TypeDragLink,         // Only supported on OS X 10.6 and up
+    TypeIBeam,
+    TypeNotAllowed,       // Only supported on OS X 10.6 and up
+    TypeOpenHand,
+    TypePointingHand,
+    TypeResizeDown,
+    TypeResizeLeft,
+    TypeResizeLeftRight,
+    TypeResizeRight,
+    TypeResizeUp,
+    TypeResizeUpDown,
+    TypeTransparent       // Special type
+  };
+
+  NSCursorInfo();
+  explicit NSCursorInfo(NSCursor* aCursor);
+  explicit NSCursorInfo(const Cursor* aCursor);
+  ~NSCursorInfo();
+
+  NSCursor* GetNSCursor() const;
+  Type GetType() const;
+  const char* GetTypeName() const;
+  nsPoint GetHotSpot() const;
+  uint8_t* GetCustomImageData() const;
+  uint32_t GetCustomImageDataLength() const;
+
+  void SetType(Type aType);
+  void SetHotSpot(nsPoint aHotSpot);
+  void SetCustomImageData(uint8_t* aData, uint32_t aDataLength);
+
+  static bool GetNativeCursorsSupported();
+
+private:
+  NSCursor* GetTransparentCursor() const;
+
+  Type mType;
+  // The hot spot's coordinate system is the cursor's coordinate system, and
+  // has an upper-left origin (in both Cocoa and pre-Cocoa systems).
+  nsPoint mHotSpot;
+  uint8_t* mCustomImageData;
+  uint32_t mCustomImageDataLength;
+  static int32_t mNativeCursorsSupported;
+};
+
+namespace parent {
+
+void OnPluginShowWindow(uint32_t window_id, CGRect window_bounds, bool modal);
+void OnPluginHideWindow(uint32_t window_id, pid_t aPluginPid);
+void OnSetCursor(const NSCursorInfo& cursorInfo);
+void OnShowCursor(bool show);
+void OnPushCursor(const NSCursorInfo& cursorInfo);
+void OnPopCursor();
+
+} // namespace parent
+
+namespace child {
+
+void SetUpCocoaInterposing();
+
+} // namespace child
+
+} // namespace mac_plugin_interposing
+
+#endif /* DOM_PLUGINS_IPC_PLUGININTERPOSEOSX_H */
diff --git a/dom/plugins/ipc/PluginInterposeOSX.mm b/dom/plugins/ipc/PluginInterposeOSX.mm
new file mode 100644
index 0000000000..bf24d2b0d8
--- /dev/null
+++ b/dom/plugins/ipc/PluginInterposeOSX.mm
@@ -0,0 +1,1158 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+// vim:set ts=2 sts=2 sw=2 et cin:
+// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "base/basictypes.h"
+#include "nsCocoaUtils.h"
+#include "PluginModuleChild.h"
+#include "nsDebug.h"
+#include "PluginInterposeOSX.h"
+#include <set>
+#import <AppKit/AppKit.h>
+#import <objc/runtime.h>
+#import <Carbon/Carbon.h>
+
+using namespace mozilla::plugins;
+
+namespace mac_plugin_interposing {
+
+int32_t NSCursorInfo::mNativeCursorsSupported = -1;
+
+// This constructor may be called from the browser process or the plugin
+// process.
+NSCursorInfo::NSCursorInfo()
+  : mType(TypeArrow)
+  , mHotSpot(nsPoint(0, 0))
+  , mCustomImageData(NULL)
+  , mCustomImageDataLength(0)
+{
+}
+
+NSCursorInfo::NSCursorInfo(NSCursor* aCursor)
+  : mType(TypeArrow)
+  , mHotSpot(nsPoint(0, 0))
+  , mCustomImageData(NULL)
+  , mCustomImageDataLength(0)
+{
+  // This constructor is only ever called from the plugin process, so the
+  // following is safe.
+  if (!GetNativeCursorsSupported()) {
+    return;
+  }
+
+  NSPoint hotSpotCocoa = [aCursor hotSpot];
+  mHotSpot = nsPoint(hotSpotCocoa.x, hotSpotCocoa.y);
+
+  Class nsCursorClass = [NSCursor class];
+  if ([aCursor isEqual:[NSCursor arrowCursor]]) {
+    mType = TypeArrow;
+  } else if ([aCursor isEqual:[NSCursor closedHandCursor]]) {
+    mType = TypeClosedHand;
+  } else if ([aCursor isEqual:[NSCursor crosshairCursor]]) {
+    mType = TypeCrosshair;
+  } else if ([aCursor isEqual:[NSCursor disappearingItemCursor]]) {
+    mType = TypeDisappearingItem;
+  } else if ([aCursor isEqual:[NSCursor IBeamCursor]]) {
+    mType = TypeIBeam;
+  } else if ([aCursor isEqual:[NSCursor openHandCursor]]) {
+    mType = TypeOpenHand;
+  } else if ([aCursor isEqual:[NSCursor pointingHandCursor]]) {
+    mType = TypePointingHand;
+  } else if ([aCursor isEqual:[NSCursor resizeDownCursor]]) {
+    mType = TypeResizeDown;
+  } else if ([aCursor isEqual:[NSCursor resizeLeftCursor]]) {
+    mType = TypeResizeLeft;
+  } else if ([aCursor isEqual:[NSCursor resizeLeftRightCursor]]) {
+    mType = TypeResizeLeftRight;
+  } else if ([aCursor isEqual:[NSCursor resizeRightCursor]]) {
+    mType = TypeResizeRight;
+  } else if ([aCursor isEqual:[NSCursor resizeUpCursor]]) {
+    mType = TypeResizeUp;
+  } else if ([aCursor isEqual:[NSCursor resizeUpDownCursor]]) {
+    mType = TypeResizeUpDown;
+  // The following cursor types are only supported on OS X 10.6 and up.
+  } else if ([nsCursorClass respondsToSelector:@selector(contextualMenuCursor)] &&
+             [aCursor isEqual:[nsCursorClass performSelector:@selector(contextualMenuCursor)]]) {
+    mType = TypeContextualMenu;
+  } else if ([nsCursorClass respondsToSelector:@selector(dragCopyCursor)] &&
+             [aCursor isEqual:[nsCursorClass performSelector:@selector(dragCopyCursor)]]) {
+    mType = TypeDragCopy;
+  } else if ([nsCursorClass respondsToSelector:@selector(dragLinkCursor)] &&
+             [aCursor isEqual:[nsCursorClass performSelector:@selector(dragLinkCursor)]]) {
+    mType = TypeDragLink;
+  } else if ([nsCursorClass respondsToSelector:@selector(operationNotAllowedCursor)] &&
+             [aCursor isEqual:[nsCursorClass performSelector:@selector(operationNotAllowedCursor)]]) {
+    mType = TypeNotAllowed;
+  } else {
+    NSImage* image = [aCursor image];
+    NSArray* reps = image ? [image representations] : nil;
+    NSUInteger repsCount = reps ? [reps count] : 0;
+    if (!repsCount) {
+      // If we have a custom cursor with no image representations, assume we
+      // need a transparent cursor.
+      mType = TypeTransparent;
+    } else {
+      CGImageRef cgImage = nil;
+      // XXX We don't know how to deal with a cursor that doesn't have a
+      //     bitmap image representation.  For now we fall back to an arrow
+      //     cursor.
+      for (NSUInteger i = 0; i < repsCount; ++i) {
+        id rep = [reps objectAtIndex:i];
+        if ([rep isKindOfClass:[NSBitmapImageRep class]]) {
+          cgImage = [(NSBitmapImageRep*)rep CGImage];
+          break;
+        }
+      }
+      if (cgImage) {
+        CFMutableDataRef data = ::CFDataCreateMutable(kCFAllocatorDefault, 0);
+        if (data) {
+          CGImageDestinationRef dest = ::CGImageDestinationCreateWithData(data,
+                                                                          kUTTypePNG,
+                                                                          1,
+                                                                          NULL);
+          if (dest) {
+            ::CGImageDestinationAddImage(dest, cgImage, NULL);
+            if (::CGImageDestinationFinalize(dest)) {
+              uint32_t dataLength = (uint32_t) ::CFDataGetLength(data);
+              mCustomImageData = (uint8_t*) moz_xmalloc(dataLength);
+              ::CFDataGetBytes(data, ::CFRangeMake(0, dataLength), mCustomImageData);
+              mCustomImageDataLength = dataLength;
+              mType = TypeCustom;
+            }
+            ::CFRelease(dest);
+          }
+          ::CFRelease(data);
+        }
+      }
+      if (!mCustomImageData) {
+        mType = TypeArrow;
+      }
+    }
+  }
+}
+
+NSCursorInfo::NSCursorInfo(const Cursor* aCursor)
+  : mType(TypeArrow)
+  , mHotSpot(nsPoint(0, 0))
+  , mCustomImageData(NULL)
+  , mCustomImageDataLength(0)
+{
+  // This constructor is only ever called from the plugin process, so the
+  // following is safe.
+  if (!GetNativeCursorsSupported()) {
+    return;
+  }
+
+  mHotSpot = nsPoint(aCursor->hotSpot.h, aCursor->hotSpot.v);
+
+  int width = 16, height = 16;
+  int bytesPerPixel = 4;
+  int rowBytes = width * bytesPerPixel;
+  int bitmapSize = height * rowBytes;
+
+  bool isTransparent = true;
+
+  uint8_t* bitmap = (uint8_t*) moz_xmalloc(bitmapSize);
+  // The way we create 'bitmap' is largely "borrowed" from Chrome's
+  // WebCursor::InitFromCursor().
+  for (int y = 0; y < height; ++y) {
+    unsigned short data = aCursor->data[y];
+    unsigned short mask = aCursor->mask[y];
+    // Change 'data' and 'mask' from big-endian to little-endian, but output
+    // big-endian data below.
+    data = ((data << 8) & 0xFF00) | ((data >> 8) & 0x00FF);
+    mask = ((mask << 8) & 0xFF00) | ((mask >> 8) & 0x00FF);
+    // It'd be nice to use a gray-scale bitmap.  But
+    // CGBitmapContextCreateImage() (used below) won't work with one that also
+    // has alpha values.
+    for (int x = 0; x < width; ++x) {
+      int offset = (y * rowBytes) + (x * bytesPerPixel);
+      // Color value
+      if (data & 0x8000) {
+        bitmap[offset]     = 0x0;
+        bitmap[offset + 1] = 0x0;
+        bitmap[offset + 2] = 0x0;
+      } else {
+        bitmap[offset]     = 0xFF;
+        bitmap[offset + 1] = 0xFF;
+        bitmap[offset + 2] = 0xFF;
+      }
+      // Mask value
+      if (mask & 0x8000) {
+        bitmap[offset + 3] = 0xFF;
+        isTransparent = false;
+      } else {
+        bitmap[offset + 3] = 0x0;
+      }
+      data <<= 1;
+      mask <<= 1;
+    }
+  }
+
+  if (isTransparent) {
+    // If aCursor is transparent, we don't need to serialize custom cursor
+    // data over IPC.
+    mType = TypeTransparent;
+  } else {
+    CGColorSpaceRef color = ::CGColorSpaceCreateDeviceRGB();
+    if (color) {
+      CGContextRef context =
+        ::CGBitmapContextCreate(bitmap,
+                                width,
+                                height,
+                                8,
+                                rowBytes,
+                                color,
+                                kCGImageAlphaPremultipliedLast |
+                                  kCGBitmapByteOrder32Big);
+      if (context) {
+        CGImageRef image = ::CGBitmapContextCreateImage(context);
+        if (image) {
+          ::CFMutableDataRef data = ::CFDataCreateMutable(kCFAllocatorDefault, 0);
+          if (data) {
+            CGImageDestinationRef dest =
+              ::CGImageDestinationCreateWithData(data,
+                                                 kUTTypePNG,
+                                                 1,
+                                                 NULL);
+            if (dest) {
+              ::CGImageDestinationAddImage(dest, image, NULL);
+              if (::CGImageDestinationFinalize(dest)) {
+                uint32_t dataLength = (uint32_t) ::CFDataGetLength(data);
+                mCustomImageData = (uint8_t*) moz_xmalloc(dataLength);
+                ::CFDataGetBytes(data,
+                                 ::CFRangeMake(0, dataLength),
+                                 mCustomImageData);
+                mCustomImageDataLength = dataLength;
+                mType = TypeCustom;
+              }
+              ::CFRelease(dest);
+            }
+            ::CFRelease(data);
+          }
+          ::CGImageRelease(image);
+        }
+        ::CGContextRelease(context);
+      }
+      ::CGColorSpaceRelease(color);
+    }
+  }
+
+  free(bitmap);
+}
+
+NSCursorInfo::~NSCursorInfo()
+{
+  if (mCustomImageData) {
+    free(mCustomImageData);
+  }
+}
+
+NSCursor* NSCursorInfo::GetNSCursor() const
+{
+  NSCursor* retval = nil;
+
+  Class nsCursorClass = [NSCursor class];
+  switch(mType) {
+    case TypeArrow:
+      retval = [NSCursor arrowCursor];
+      break;
+    case TypeClosedHand:
+      retval = [NSCursor closedHandCursor];
+      break;
+    case TypeCrosshair:
+      retval = [NSCursor crosshairCursor];
+      break;
+    case TypeDisappearingItem:
+      retval = [NSCursor disappearingItemCursor];
+      break;
+    case TypeIBeam:
+      retval = [NSCursor IBeamCursor];
+      break;
+    case TypeOpenHand:
+      retval = [NSCursor openHandCursor];
+      break;
+    case TypePointingHand:
+      retval = [NSCursor pointingHandCursor];
+      break;
+    case TypeResizeDown:
+      retval = [NSCursor resizeDownCursor];
+      break;
+    case TypeResizeLeft:
+      retval = [NSCursor resizeLeftCursor];
+      break;
+    case TypeResizeLeftRight:
+      retval = [NSCursor resizeLeftRightCursor];
+      break;
+    case TypeResizeRight:
+      retval = [NSCursor resizeRightCursor];
+      break;
+    case TypeResizeUp:
+      retval = [NSCursor resizeUpCursor];
+      break;
+    case TypeResizeUpDown:
+      retval = [NSCursor resizeUpDownCursor];
+      break;
+    // The following four cursor types are only supported on OS X 10.6 and up.
+    case TypeContextualMenu: {
+      if ([nsCursorClass respondsToSelector:@selector(contextualMenuCursor)]) {
+        retval = [nsCursorClass performSelector:@selector(contextualMenuCursor)];
+      }
+      break;
+    }
+    case TypeDragCopy: {
+      if ([nsCursorClass respondsToSelector:@selector(dragCopyCursor)]) {
+        retval = [nsCursorClass performSelector:@selector(dragCopyCursor)];
+      }
+      break;
+    }
+    case TypeDragLink: {
+      if ([nsCursorClass respondsToSelector:@selector(dragLinkCursor)]) {
+        retval = [nsCursorClass performSelector:@selector(dragLinkCursor)];
+      }
+      break;
+    }
+    case TypeNotAllowed: {
+      if ([nsCursorClass respondsToSelector:@selector(operationNotAllowedCursor)]) {
+        retval = [nsCursorClass performSelector:@selector(operationNotAllowedCursor)];
+      }
+      break;
+    }
+    case TypeTransparent:
+      retval = GetTransparentCursor();
+      break;
+    default:
+      break;
+  }
+
+  if (!retval && mCustomImageData && mCustomImageDataLength) {
+    CGDataProviderRef provider = ::CGDataProviderCreateWithData(NULL,
+                                                                (const void*)mCustomImageData,
+                                                                mCustomImageDataLength,
+                                                                NULL);
+    if (provider) {
+      CGImageRef cgImage = ::CGImageCreateWithPNGDataProvider(provider,
+                                                              NULL,
+                                                              false,
+                                                              kCGRenderingIntentDefault);
+      if (cgImage) {
+        NSBitmapImageRep* rep = [[NSBitmapImageRep alloc] initWithCGImage:cgImage];
+        if (rep) {
+          NSImage* image = [[NSImage alloc] init];
+          if (image) {
+            [image addRepresentation:rep];
+            retval = [[[NSCursor alloc] initWithImage:image 
+                                              hotSpot:NSMakePoint(mHotSpot.x, mHotSpot.y)]
+                      autorelease];
+            [image release];
+          }
+          [rep release];
+        }
+        ::CGImageRelease(cgImage);
+      }
+      ::CFRelease(provider);
+    }
+  }
+
+  // Fall back to an arrow cursor if need be.
+  if (!retval) {
+    retval = [NSCursor arrowCursor];
+  }
+
+  return retval;
+}
+
+// Get a transparent cursor with the appropriate hot spot.  We need one if
+// (for example) we have a custom cursor with no image data.
+NSCursor* NSCursorInfo::GetTransparentCursor() const
+{
+  NSCursor* retval = nil;
+
+  int width = 16, height = 16;
+  int bytesPerPixel = 2;
+  int rowBytes = width * bytesPerPixel;
+  int dataSize = height * rowBytes;
+
+  uint8_t* data = (uint8_t*) moz_xmalloc(dataSize);
+  for (int y = 0; y < height; ++y) {
+    for (int x = 0; x < width; ++x) {
+      int offset = (y * rowBytes) + (x * bytesPerPixel);
+      data[offset] = 0x7E;  // Arbitrary gray-scale value
+      data[offset + 1] = 0; // Alpha value to make us transparent
+    }
+  }
+
+  NSBitmapImageRep* imageRep =
+    [[[NSBitmapImageRep alloc] initWithBitmapDataPlanes:nil
+                                             pixelsWide:width
+                                             pixelsHigh:height
+                                          bitsPerSample:8
+                                        samplesPerPixel:2
+                                               hasAlpha:YES
+                                               isPlanar:NO
+                                         colorSpaceName:NSCalibratedWhiteColorSpace
+                                            bytesPerRow:rowBytes
+                                           bitsPerPixel:16]
+     autorelease];
+  if (imageRep) {
+    uint8_t* repDataPtr = [imageRep bitmapData];
+    if (repDataPtr) {
+      memcpy(repDataPtr, data, dataSize);
+      NSImage *image =
+        [[[NSImage alloc] initWithSize:NSMakeSize(width, height)]
+         autorelease];
+      if (image) {
+        [image addRepresentation:imageRep];
+        retval =
+          [[[NSCursor alloc] initWithImage:image
+                                   hotSpot:NSMakePoint(mHotSpot.x, mHotSpot.y)]
+           autorelease];
+      }
+    }
+  }
+
+  free(data);
+
+  // Fall back to an arrow cursor if (for some reason) the above code failed.
+  if (!retval) {
+    retval = [NSCursor arrowCursor];
+  }
+
+  return retval;
+}
+
+NSCursorInfo::Type NSCursorInfo::GetType() const
+{
+  return mType;
+}
+
+const char* NSCursorInfo::GetTypeName() const
+{
+  switch(mType) {
+    case TypeCustom:
+      return "TypeCustom";
+    case TypeArrow:
+      return "TypeArrow";
+    case TypeClosedHand:
+      return "TypeClosedHand";
+    case TypeContextualMenu:
+      return "TypeContextualMenu";
+    case TypeCrosshair:
+      return "TypeCrosshair";
+    case TypeDisappearingItem:
+      return "TypeDisappearingItem";
+    case TypeDragCopy:
+      return "TypeDragCopy";
+    case TypeDragLink:
+      return "TypeDragLink";
+    case TypeIBeam:
+      return "TypeIBeam";
+    case TypeNotAllowed:
+      return "TypeNotAllowed";
+    case TypeOpenHand:
+      return "TypeOpenHand";
+    case TypePointingHand:
+      return "TypePointingHand";
+    case TypeResizeDown:
+      return "TypeResizeDown";
+    case TypeResizeLeft:
+      return "TypeResizeLeft";
+    case TypeResizeLeftRight:
+      return "TypeResizeLeftRight";
+    case TypeResizeRight:
+      return "TypeResizeRight";
+    case TypeResizeUp:
+      return "TypeResizeUp";
+    case TypeResizeUpDown:
+      return "TypeResizeUpDown";
+    case TypeTransparent:
+      return "TypeTransparent";
+    default:
+      break;
+  }
+  return "TypeUnknown";
+}
+
+nsPoint NSCursorInfo::GetHotSpot() const
+{
+  return mHotSpot;
+}
+
+uint8_t* NSCursorInfo::GetCustomImageData() const
+{
+  return mCustomImageData;
+}
+
+uint32_t NSCursorInfo::GetCustomImageDataLength() const
+{
+  return mCustomImageDataLength;
+}
+
+void NSCursorInfo::SetType(Type aType)
+{
+  mType = aType;
+}
+
+void NSCursorInfo::SetHotSpot(nsPoint aHotSpot)
+{
+  mHotSpot = aHotSpot;
+}
+
+void NSCursorInfo::SetCustomImageData(uint8_t* aData, uint32_t aDataLength)
+{
+  if (mCustomImageData) {
+    free(mCustomImageData);
+  }
+  if (aDataLength) {
+    mCustomImageData = (uint8_t*) moz_xmalloc(aDataLength);
+    memcpy(mCustomImageData, aData, aDataLength);
+  } else {
+    mCustomImageData = NULL;
+  }
+  mCustomImageDataLength = aDataLength;
+}
+
+// This should never be called from the browser process -- only from the
+// plugin process.
+bool NSCursorInfo::GetNativeCursorsSupported()
+{
+  if (mNativeCursorsSupported == -1) {
+    ENSURE_PLUGIN_THREAD(false);
+    PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+    if (pmc) {
+      bool result = pmc->GetNativeCursorsSupported();
+      if (result) {
+        mNativeCursorsSupported = 1;
+      } else {
+        mNativeCursorsSupported = 0;
+      }
+    }
+  }
+  return (mNativeCursorsSupported == 1);
+}
+
+} // namespace mac_plugin_interposing
+
+namespace mac_plugin_interposing {
+namespace parent {
+
+// Tracks plugin windows currently visible.
+std::set<uint32_t> plugin_visible_windows_set_;
+// Tracks full screen windows currently visible.
+std::set<uint32_t> plugin_fullscreen_windows_set_;
+// Tracks modal windows currently visible.
+std::set<uint32_t> plugin_modal_windows_set_;
+
+void OnPluginShowWindow(uint32_t window_id,
+                        CGRect window_bounds,
+                        bool modal) {
+  plugin_visible_windows_set_.insert(window_id);
+
+  if (modal)
+    plugin_modal_windows_set_.insert(window_id);
+
+  CGRect main_display_bounds = ::CGDisplayBounds(CGMainDisplayID());
+
+  if (CGRectEqualToRect(window_bounds, main_display_bounds) &&
+      (plugin_fullscreen_windows_set_.find(window_id) ==
+       plugin_fullscreen_windows_set_.end())) {
+    plugin_fullscreen_windows_set_.insert(window_id);
+
+    nsCocoaUtils::HideOSChromeOnScreen(true);
+  }
+}
+
+static void ActivateProcess(pid_t pid) {
+  ProcessSerialNumber process;
+  OSStatus status = ::GetProcessForPID(pid, &process);
+
+  if (status == noErr) {
+    SetFrontProcess(&process);
+  } else {
+    NS_WARNING("Unable to get process for pid.");
+  }
+}
+
+// Must be called on the UI thread.
+// If plugin_pid is -1, the browser will be the active process on return,
+// otherwise that process will be given focus back before this function returns.
+static void ReleasePluginFullScreen(pid_t plugin_pid) {
+  // Releasing full screen only works if we are the frontmost process; grab
+  // focus, but give it back to the plugin process if requested.
+  ActivateProcess(base::GetCurrentProcId());
+
+  nsCocoaUtils::HideOSChromeOnScreen(false);
+
+  if (plugin_pid != -1) {
+    ActivateProcess(plugin_pid);
+  }
+}
+
+void OnPluginHideWindow(uint32_t window_id, pid_t aPluginPid) {
+  bool had_windows = !plugin_visible_windows_set_.empty();
+  plugin_visible_windows_set_.erase(window_id);
+  bool browser_needs_activation = had_windows &&
+      plugin_visible_windows_set_.empty();
+
+  plugin_modal_windows_set_.erase(window_id);
+  if (plugin_fullscreen_windows_set_.find(window_id) !=
+      plugin_fullscreen_windows_set_.end()) {
+    plugin_fullscreen_windows_set_.erase(window_id);
+    pid_t plugin_pid = browser_needs_activation ? -1 : aPluginPid;
+    browser_needs_activation = false;
+    ReleasePluginFullScreen(plugin_pid);
+  }
+
+  if (browser_needs_activation) {
+    ActivateProcess(getpid());
+  }
+}
+
+void OnSetCursor(const NSCursorInfo& cursorInfo)
+{
+  NSCursor* aCursor = cursorInfo.GetNSCursor();
+  if (aCursor) {
+    [aCursor set];
+  }
+}
+
+void OnShowCursor(bool show)
+{
+  if (show) {
+    [NSCursor unhide];
+  } else {
+    [NSCursor hide];
+  }
+}
+
+void OnPushCursor(const NSCursorInfo& cursorInfo)
+{
+  NSCursor* aCursor = cursorInfo.GetNSCursor();
+  if (aCursor) {
+    [aCursor push];
+  }
+}
+
+void OnPopCursor()
+{
+  [NSCursor pop];
+}
+
+} // namespace parent
+} // namespace mac_plugin_interposing
+
+namespace mac_plugin_interposing {
+namespace child {
+
+// TODO(stuartmorgan): Make this an IPC to order the plugin process above the
+// browser process only if the browser is current frontmost.
+void FocusPluginProcess() {
+  ProcessSerialNumber this_process, front_process;
+  if ((GetCurrentProcess(&this_process) != noErr) ||
+      (GetFrontProcess(&front_process) != noErr)) {
+    return;
+  }
+
+  Boolean matched = false;
+  if ((SameProcess(&this_process, &front_process, &matched) == noErr) &&
+      !matched) {
+    SetFrontProcess(&this_process);
+  }
+}
+
+void NotifyBrowserOfPluginShowWindow(uint32_t window_id, CGRect bounds,
+                                     bool modal) {
+  ENSURE_PLUGIN_THREAD_VOID();
+
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc)
+    pmc->PluginShowWindow(window_id, modal, bounds);
+}
+
+void NotifyBrowserOfPluginHideWindow(uint32_t window_id, CGRect bounds) {
+  ENSURE_PLUGIN_THREAD_VOID();
+
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc)
+    pmc->PluginHideWindow(window_id);
+}
+
+void NotifyBrowserOfSetCursor(NSCursorInfo& aCursorInfo)
+{
+  ENSURE_PLUGIN_THREAD_VOID();
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc) {
+    pmc->SetCursor(aCursorInfo);
+  }
+}
+
+void NotifyBrowserOfShowCursor(bool show)
+{
+  ENSURE_PLUGIN_THREAD_VOID();
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc) {
+    pmc->ShowCursor(show);
+  }
+}
+
+void NotifyBrowserOfPushCursor(NSCursorInfo& aCursorInfo)
+{
+  ENSURE_PLUGIN_THREAD_VOID();
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc) {
+    pmc->PushCursor(aCursorInfo);
+  }
+}
+
+void NotifyBrowserOfPopCursor()
+{
+  ENSURE_PLUGIN_THREAD_VOID();
+  PluginModuleChild *pmc = PluginModuleChild::GetChrome();
+  if (pmc) {
+    pmc->PopCursor();
+  }
+}
+
+struct WindowInfo {
+  uint32_t window_id;
+  CGRect bounds;
+  explicit WindowInfo(NSWindow* aWindow) {
+    NSInteger window_num = [aWindow windowNumber];
+    window_id = window_num > 0 ? window_num : 0;
+    bounds = NSRectToCGRect([aWindow frame]);
+  }
+};
+
+static void OnPluginWindowClosed(const WindowInfo& window_info) {
+  if (window_info.window_id == 0)
+    return;
+  mac_plugin_interposing::child::NotifyBrowserOfPluginHideWindow(window_info.window_id,
+                                                                 window_info.bounds);
+}
+
+static void OnPluginWindowShown(const WindowInfo& window_info, BOOL is_modal) {
+  // The window id is 0 if it has never been shown (including while it is the
+  // process of being shown for the first time); when that happens, we'll catch
+  // it in _setWindowNumber instead.
+  static BOOL s_pending_display_is_modal = NO;
+  if (window_info.window_id == 0) {
+    if (is_modal)
+      s_pending_display_is_modal = YES;
+    return;
+  }
+  if (s_pending_display_is_modal) {
+    is_modal = YES;
+    s_pending_display_is_modal = NO;
+  }
+  mac_plugin_interposing::child::NotifyBrowserOfPluginShowWindow(
+    window_info.window_id, window_info.bounds, is_modal);
+}
+
+static BOOL OnSetCursor(NSCursorInfo &aInfo)
+{
+  if (NSCursorInfo::GetNativeCursorsSupported()) {
+    NotifyBrowserOfSetCursor(aInfo);
+    return YES;
+  }
+  return NO;
+}
+
+static BOOL OnHideCursor()
+{
+  if (NSCursorInfo::GetNativeCursorsSupported()) {
+    NotifyBrowserOfShowCursor(NO);
+    return YES;
+  }
+  return NO;
+}
+
+static BOOL OnUnhideCursor()
+{
+  if (NSCursorInfo::GetNativeCursorsSupported()) {
+    NotifyBrowserOfShowCursor(YES);
+    return YES;
+  }
+  return NO;
+}
+
+static BOOL OnPushCursor(NSCursorInfo &aInfo)
+{
+  if (NSCursorInfo::GetNativeCursorsSupported()) {
+    NotifyBrowserOfPushCursor(aInfo);
+    return YES;
+  }
+  return NO;
+}
+
+static BOOL OnPopCursor()
+{
+  if (NSCursorInfo::GetNativeCursorsSupported()) {
+    NotifyBrowserOfPopCursor();
+    return YES;
+  }
+  return NO;
+}
+
+} // namespace child
+} // namespace mac_plugin_interposing
+
+using namespace mac_plugin_interposing::child;
+
+@interface NSWindow (PluginInterposing)
+- (void)pluginInterpose_orderOut:(id)sender;
+- (void)pluginInterpose_orderFront:(id)sender;
+- (void)pluginInterpose_makeKeyAndOrderFront:(id)sender;
+- (void)pluginInterpose_setWindowNumber:(NSInteger)num;
+@end
+
+@implementation NSWindow (PluginInterposing)
+
+- (void)pluginInterpose_orderOut:(id)sender {
+  WindowInfo window_info(self);
+  [self pluginInterpose_orderOut:sender];
+  OnPluginWindowClosed(window_info);
+}
+
+- (void)pluginInterpose_orderFront:(id)sender {
+  mac_plugin_interposing::child::FocusPluginProcess();
+  [self pluginInterpose_orderFront:sender];
+  OnPluginWindowShown(WindowInfo(self), NO);
+}
+
+- (void)pluginInterpose_makeKeyAndOrderFront:(id)sender {
+  mac_plugin_interposing::child::FocusPluginProcess();
+  [self pluginInterpose_makeKeyAndOrderFront:sender];
+  OnPluginWindowShown(WindowInfo(self), NO);
+}
+
+- (void)pluginInterpose_setWindowNumber:(NSInteger)num {
+  if (num > 0)
+    mac_plugin_interposing::child::FocusPluginProcess();
+  [self pluginInterpose_setWindowNumber:num];
+  if (num > 0)
+    OnPluginWindowShown(WindowInfo(self), NO);
+}
+
+@end
+
+@interface NSApplication (PluginInterposing)
+- (NSInteger)pluginInterpose_runModalForWindow:(NSWindow*)window;
+@end
+
+@implementation NSApplication (PluginInterposing)
+
+- (NSInteger)pluginInterpose_runModalForWindow:(NSWindow*)window {
+  mac_plugin_interposing::child::FocusPluginProcess();
+  // This is out-of-order relative to the other calls, but runModalForWindow:
+  // won't return until the window closes, and the order only matters for
+  // full-screen windows.
+  OnPluginWindowShown(WindowInfo(window), YES);
+  return [self pluginInterpose_runModalForWindow:window];
+}
+
+@end
+
+// Hook commands to manipulate the current cursor, so that they can be passed
+// from the child process to the parent process.  These commands have no
+// effect unless they're performed in the parent process.
+@interface NSCursor (PluginInterposing)
+- (void)pluginInterpose_set;
+- (void)pluginInterpose_push;
+- (void)pluginInterpose_pop;
++ (NSCursor*)pluginInterpose_currentCursor;
++ (void)pluginInterpose_hide;
++ (void)pluginInterpose_unhide;
++ (void)pluginInterpose_pop;
+@end
+
+// Cache the results of [NSCursor set], [NSCursor push] and [NSCursor pop].
+// The last element is always the current cursor.
+static NSMutableArray* gCursorStack = nil;
+
+static BOOL initCursorStack()
+{
+  if (!gCursorStack) {
+    gCursorStack = [[NSMutableArray arrayWithCapacity:5] retain];
+  }
+  return (gCursorStack != NULL);
+}
+
+static NSCursor* currentCursorFromCache()
+{
+  if (!initCursorStack())
+    return nil;
+  return (NSCursor*) [gCursorStack lastObject];
+}
+
+static void setCursorInCache(NSCursor* aCursor)
+{
+  if (!initCursorStack() || !aCursor)
+    return;
+  NSUInteger count = [gCursorStack count];
+  if (count) {
+    [gCursorStack replaceObjectAtIndex:count - 1 withObject:aCursor];
+  } else {
+    [gCursorStack addObject:aCursor];
+  }
+}
+
+static void pushCursorInCache(NSCursor* aCursor)
+{
+  if (!initCursorStack() || !aCursor)
+    return;
+  [gCursorStack addObject:aCursor];
+}
+
+static void popCursorInCache()
+{
+  if (!initCursorStack())
+    return;
+  // Apple's doc on the +[NSCursor pop] method says:  "If the current cursor
+  // is the only cursor on the stack, this method does nothing."
+  if ([gCursorStack count] > 1) {
+    [gCursorStack removeLastObject];
+  }
+}
+
+@implementation NSCursor (PluginInterposing)
+
+- (void)pluginInterpose_set
+{
+  NSCursorInfo info(self);
+  OnSetCursor(info);
+  setCursorInCache(self);
+  [self pluginInterpose_set];
+}
+
+- (void)pluginInterpose_push
+{
+  NSCursorInfo info(self);
+  OnPushCursor(info);
+  pushCursorInCache(self);
+  [self pluginInterpose_push];
+}
+
+- (void)pluginInterpose_pop
+{
+  OnPopCursor();
+  popCursorInCache();
+  [self pluginInterpose_pop];
+}
+
+// The currentCursor method always returns nil when running in a background
+// process.  But this may confuse plugins (notably Flash, see bug 621117).  So
+// if we get a nil return from the "call to super", we return a cursor that's
+// been cached by previous calls to set or push.  According to Apple's docs,
+// currentCursor "only returns the cursor set by your application using
+// NSCursor methods".  So we don't need to worry about changes to the cursor
+// made by other methods like SetThemeCursor().
++ (NSCursor*)pluginInterpose_currentCursor
+{
+  NSCursor* retval = [self pluginInterpose_currentCursor];
+  if (!retval) {
+    retval = currentCursorFromCache();
+  }
+  return retval;
+}
+
++ (void)pluginInterpose_hide
+{
+  OnHideCursor();
+  [self pluginInterpose_hide];
+}
+
++ (void)pluginInterpose_unhide
+{
+  OnUnhideCursor();
+  [self pluginInterpose_unhide];
+}
+
++ (void)pluginInterpose_pop
+{
+  OnPopCursor();
+  popCursorInCache();
+  [self pluginInterpose_pop];
+}
+
+@end
+
+static void ExchangeMethods(Class target_class,
+                            BOOL class_method,
+                            SEL original,
+                            SEL replacement) {
+  Method m1;
+  Method m2;
+  if (class_method) {
+    m1 = class_getClassMethod(target_class, original);
+    m2 = class_getClassMethod(target_class, replacement);
+  } else {
+    m1 = class_getInstanceMethod(target_class, original);
+    m2 = class_getInstanceMethod(target_class, replacement);
+  }
+
+  if (m1 == m2)
+    return;
+
+  if (m1 && m2)
+    method_exchangeImplementations(m1, m2);
+  else
+    NS_NOTREACHED("Cocoa swizzling failed");
+}
+
+namespace mac_plugin_interposing {
+namespace child {
+
+void SetUpCocoaInterposing() {
+  Class nswindow_class = [NSWindow class];
+  ExchangeMethods(nswindow_class, NO, @selector(orderOut:),
+                  @selector(pluginInterpose_orderOut:));
+  ExchangeMethods(nswindow_class, NO, @selector(orderFront:),
+                  @selector(pluginInterpose_orderFront:));
+  ExchangeMethods(nswindow_class, NO, @selector(makeKeyAndOrderFront:),
+                  @selector(pluginInterpose_makeKeyAndOrderFront:));
+  ExchangeMethods(nswindow_class, NO, @selector(_setWindowNumber:),
+                  @selector(pluginInterpose_setWindowNumber:));
+
+  ExchangeMethods([NSApplication class], NO, @selector(runModalForWindow:),
+                  @selector(pluginInterpose_runModalForWindow:));
+
+  Class nscursor_class = [NSCursor class];
+  ExchangeMethods(nscursor_class, NO, @selector(set),
+                  @selector(pluginInterpose_set));
+  ExchangeMethods(nscursor_class, NO, @selector(push),
+                  @selector(pluginInterpose_push));
+  ExchangeMethods(nscursor_class, NO, @selector(pop),
+                  @selector(pluginInterpose_pop));
+  ExchangeMethods(nscursor_class, YES, @selector(currentCursor),
+                  @selector(pluginInterpose_currentCursor));
+  ExchangeMethods(nscursor_class, YES, @selector(hide),
+                  @selector(pluginInterpose_hide));
+  ExchangeMethods(nscursor_class, YES, @selector(unhide),
+                  @selector(pluginInterpose_unhide));
+  ExchangeMethods(nscursor_class, YES, @selector(pop),
+                  @selector(pluginInterpose_pop));
+}
+
+}  // namespace child
+}  // namespace mac_plugin_interposing
+
+// Called from plugin_child_interpose.mm, which hooks calls to
+// SetCursor() (the QuickDraw call) from the plugin child process.
+extern "C" NS_VISIBILITY_DEFAULT BOOL
+mac_plugin_interposing_child_OnSetCursor(const Cursor* cursor)
+{
+  NSCursorInfo info(cursor);
+  return OnSetCursor(info);
+}
+
+// Called from plugin_child_interpose.mm, which hooks calls to
+// SetThemeCursor() (the Appearance Manager call) from the plugin child
+// process.
+extern "C" NS_VISIBILITY_DEFAULT BOOL
+mac_plugin_interposing_child_OnSetThemeCursor(ThemeCursor cursor)
+{
+  NSCursorInfo info;
+  switch (cursor) {
+    case kThemeArrowCursor:
+      info.SetType(NSCursorInfo::TypeArrow);
+      break;
+    case kThemeCopyArrowCursor:
+      info.SetType(NSCursorInfo::TypeDragCopy);
+      break;
+    case kThemeAliasArrowCursor:
+      info.SetType(NSCursorInfo::TypeDragLink);
+      break;
+    case kThemeContextualMenuArrowCursor:
+      info.SetType(NSCursorInfo::TypeContextualMenu);
+      break;
+    case kThemeIBeamCursor:
+      info.SetType(NSCursorInfo::TypeIBeam);
+      break;
+    case kThemeCrossCursor:
+    case kThemePlusCursor:
+      info.SetType(NSCursorInfo::TypeCrosshair);
+      break;
+    case kThemeWatchCursor:
+    case kThemeSpinningCursor:
+      info.SetType(NSCursorInfo::TypeArrow);
+      break;
+    case kThemeClosedHandCursor:
+      info.SetType(NSCursorInfo::TypeClosedHand);
+      break;
+    case kThemeOpenHandCursor:
+      info.SetType(NSCursorInfo::TypeOpenHand);
+      break;
+    case kThemePointingHandCursor:
+    case kThemeCountingUpHandCursor:
+    case kThemeCountingDownHandCursor:
+    case kThemeCountingUpAndDownHandCursor:
+      info.SetType(NSCursorInfo::TypePointingHand);
+      break;
+    case kThemeResizeLeftCursor:
+      info.SetType(NSCursorInfo::TypeResizeLeft);
+      break;
+    case kThemeResizeRightCursor:
+      info.SetType(NSCursorInfo::TypeResizeRight);
+      break;
+    case kThemeResizeLeftRightCursor:
+      info.SetType(NSCursorInfo::TypeResizeLeftRight);
+      break;
+    case kThemeNotAllowedCursor:
+      info.SetType(NSCursorInfo::TypeNotAllowed);
+      break;
+    case kThemeResizeUpCursor:
+      info.SetType(NSCursorInfo::TypeResizeUp);
+      break;
+    case kThemeResizeDownCursor:
+      info.SetType(NSCursorInfo::TypeResizeDown);
+      break;
+    case kThemeResizeUpDownCursor:
+      info.SetType(NSCursorInfo::TypeResizeUpDown);
+      break;
+    case kThemePoofCursor:
+      info.SetType(NSCursorInfo::TypeDisappearingItem);
+      break;
+    default:
+      info.SetType(NSCursorInfo::TypeArrow);
+      break;
+  }
+  return OnSetCursor(info);
+}
+
+extern "C" NS_VISIBILITY_DEFAULT BOOL
+mac_plugin_interposing_child_OnHideCursor()
+{
+  return OnHideCursor();
+}
+
+extern "C" NS_VISIBILITY_DEFAULT BOOL
+mac_plugin_interposing_child_OnShowCursor()
+{
+  return OnUnhideCursor();
+}
diff --git a/dom/plugins/ipc/PluginLibrary.h b/dom/plugins/ipc/PluginLibrary.h
index 50182d0b0d..2f9a3f81b2 100644
--- a/dom/plugins/ipc/PluginLibrary.h
+++ b/dom/plugins/ipc/PluginLibrary.h
@@ -57,7 +57,7 @@ public:
 
   virtual bool HasRequiredFunctions() = 0;
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
   virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPPluginFuncs* pFuncs, NPError* error) = 0;
 #else
   virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error) = 0;
@@ -66,7 +66,7 @@ public:
   virtual nsresult NP_GetMIMEDescription(const char** mimeDesc) = 0;
   virtual nsresult NP_GetValue(void *future, NPPVariable aVariable,
                                void *aValue, NPError* error) = 0;
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
   virtual nsresult NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error) = 0;
 #endif
   virtual nsresult NPP_New(NPMIMEType pluginType, NPP instance,
@@ -83,7 +83,10 @@ public:
   virtual nsresult GetImageSize(NPP instance, nsIntSize* aSize) = 0;
   virtual void DidComposite(NPP instance) = 0;
   virtual bool IsOOP() = 0;
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+  virtual nsresult IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing) = 0;
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
   virtual nsresult ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor) = 0;
 #endif
 #if defined(XP_WIN)
diff --git a/dom/plugins/ipc/PluginMessageUtils.cpp b/dom/plugins/ipc/PluginMessageUtils.cpp
index 9b27c76d5a..be1b2d15a5 100644
--- a/dom/plugins/ipc/PluginMessageUtils.cpp
+++ b/dom/plugins/ipc/PluginMessageUtils.cpp
@@ -49,10 +49,13 @@ namespace plugins {
 
 NPRemoteWindow::NPRemoteWindow() :
   window(0), x(0), y(0), width(0), height(0), type(NPWindowTypeDrawable)
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
   , visualID(0)
   , colormap(0)
 #endif /* XP_UNIX */
+#if defined(XP_MACOSX)
+  ,contentsScaleFactor(1.0)
+#endif
 {
   clipRect.top = 0;
   clipRect.left = 0;
diff --git a/dom/plugins/ipc/PluginMessageUtils.h b/dom/plugins/ipc/PluginMessageUtils.h
index e04e906382..a9cd52ae29 100644
--- a/dom/plugins/ipc/PluginMessageUtils.h
+++ b/dom/plugins/ipc/PluginMessageUtils.h
@@ -1,4 +1,5 @@
 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=4 ts=4 et :
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -22,7 +23,11 @@
 #include "nsTArray.h"
 #include "mozilla/Logging.h"
 #include "nsHashKeys.h"
+#ifdef XP_MACOSX
+#include "PluginInterposeOSX.h"
+#else
 namespace mac_plugin_interposing { class NSCursorInfo { }; }
+#endif
 using mac_plugin_interposing::NSCursorInfo;
 
 namespace mozilla {
@@ -82,24 +87,24 @@ struct NPRemoteWindow
   uint32_t height;
   NPRect clipRect;
   NPWindowType type;
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
   VisualID visualID;
   Colormap colormap;
 #endif /* XP_UNIX */
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
   double contentsScaleFactor;
 #endif
 };
 
-// This struct is like NPAudioDeviceChangeDetails, only it uses a
-// std::wstring instead of a const wchar_t* for the defaultDevice.
-// This gives us the necessary memory-ownership semantics without
-// requiring C++ objects in npapi.h.
-struct NPAudioDeviceChangeDetailsIPC
-{
-  int32_t flow;
-  int32_t role;
-  std::wstring defaultDevice;
+// This struct is like NPAudioDeviceChangeDetails, only it uses a

+// std::wstring instead of a const wchar_t* for the defaultDevice.

+// This gives us the necessary memory-ownership semantics without

+// requiring C++ objects in npapi.h.

+struct NPAudioDeviceChangeDetailsIPC

+{

+  int32_t flow;

+  int32_t role;

+  std::wstring defaultDevice;

 };
 
 #ifdef XP_WIN
@@ -151,6 +156,11 @@ NPPVariableToString(NPPVariable aVar)
   
         VARSTR(NPPVpluginWantsAllNetworkStreams);
 
+#ifdef XP_MACOSX
+        VARSTR(NPPVpluginDrawingModel);
+        VARSTR(NPPVpluginEventModel);
+#endif
+
 #ifdef XP_WIN
         VARSTR(NPPVpluginRequiresAudioDeviceChanges);
 #endif
@@ -347,11 +357,11 @@ struct ParamTraits<mozilla::plugins::NPRemoteWindow>
     WriteParam(aMsg, aParam.height);
     WriteParam(aMsg, aParam.clipRect);
     WriteParam(aMsg, aParam.type);
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     aMsg->WriteULong(aParam.visualID);
     aMsg->WriteULong(aParam.colormap);
 #endif
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     aMsg->WriteDouble(aParam.contentsScaleFactor);
 #endif
   }
@@ -372,7 +382,7 @@ struct ParamTraits<mozilla::plugins::NPRemoteWindow>
           ReadParam(aMsg, aIter, &type)))
       return false;
 
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     unsigned long visualID;
     unsigned long colormap;
     if (!(aMsg->ReadULong(aIter, &visualID) &&
@@ -380,7 +390,7 @@ struct ParamTraits<mozilla::plugins::NPRemoteWindow>
       return false;
 #endif
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     double contentsScaleFactor;
     if (!aMsg->ReadDouble(aIter, &contentsScaleFactor))
       return false;
@@ -393,11 +403,11 @@ struct ParamTraits<mozilla::plugins::NPRemoteWindow>
     aResult->height = height;
     aResult->clipRect = clipRect;
     aResult->type = type;
-#if defined(MOZ_X11) && defined(XP_UNIX)
+#if defined(MOZ_X11) && defined(XP_UNIX) && !defined(XP_MACOSX)
     aResult->visualID = visualID;
     aResult->colormap = colormap;
 #endif
-#if defined(XP_WIN)
+#if defined(XP_MACOSX) || defined(XP_WIN)
     aResult->contentsScaleFactor = contentsScaleFactor;
 #endif
     return true;
@@ -412,6 +422,161 @@ struct ParamTraits<mozilla::plugins::NPRemoteWindow>
   }
 };
 
+#ifdef XP_MACOSX
+template <>
+struct ParamTraits<NPNSString*>
+{
+  typedef NPNSString* paramType;
+
+  // Empty string writes a length of 0 and no buffer.
+  // We don't write a nullptr terminating character in buffers.
+  static void Write(Message* aMsg, const paramType& aParam)
+  {
+    CFStringRef cfString = (CFStringRef)aParam;
+
+    // Write true if we have a string, false represents nullptr.
+    aMsg->WriteBool(!!cfString);
+    if (!cfString) {
+      return;
+    }
+
+    long length = ::CFStringGetLength(cfString);
+    WriteParam(aMsg, length);
+    if (length == 0) {
+      return;
+    }
+
+    // Attempt to get characters without any allocation/conversion.
+    if (::CFStringGetCharactersPtr(cfString)) {
+      aMsg->WriteBytes(::CFStringGetCharactersPtr(cfString), length * sizeof(UniChar));
+    } else {
+      UniChar *buffer = (UniChar*)moz_xmalloc(length * sizeof(UniChar));
+      ::CFStringGetCharacters(cfString, ::CFRangeMake(0, length), buffer);
+      aMsg->WriteBytes(buffer, length * sizeof(UniChar));
+      free(buffer);
+    }
+  }
+
+  static bool Read(const Message* aMsg, PickleIterator* aIter, paramType* aResult)
+  {
+    bool haveString = false;
+    if (!aMsg->ReadBool(aIter, &haveString)) {
+      return false;
+    }
+    if (!haveString) {
+      *aResult = nullptr;
+      return true;
+    }
+
+    long length;
+    if (!ReadParam(aMsg, aIter, &length)) {
+      return false;
+    }
+
+    // Avoid integer multiplication overflow.
+    if (length > INT_MAX / static_cast<long>(sizeof(UniChar))) {
+      return false;
+    }
+
+    auto chars = mozilla::MakeUnique<UniChar[]>(length);
+    if (length != 0) {
+      if (!aMsg->ReadBytesInto(aIter, chars.get(), length * sizeof(UniChar))) {
+        return false;
+      }
+    }
+
+    *aResult = (NPNSString*)::CFStringCreateWithBytes(kCFAllocatorDefault, (UInt8*)chars.get(),
+                                                      length * sizeof(UniChar),
+                                                      kCFStringEncodingUTF16, false);
+    if (!*aResult) {
+      return false;
+    }
+
+    return true;
+  }
+};
+#endif
+
+#ifdef XP_MACOSX
+template <>
+struct ParamTraits<NSCursorInfo>
+{
+  typedef NSCursorInfo paramType;
+
+  static void Write(Message* aMsg, const paramType& aParam)
+  {
+    NSCursorInfo::Type type = aParam.GetType();
+
+    aMsg->WriteInt(type);
+
+    nsPoint hotSpot = aParam.GetHotSpot();
+    WriteParam(aMsg, hotSpot.x);
+    WriteParam(aMsg, hotSpot.y);
+
+    uint32_t dataLength = aParam.GetCustomImageDataLength();
+    WriteParam(aMsg, dataLength);
+    if (dataLength == 0) {
+      return;
+    }
+
+    uint8_t* buffer = (uint8_t*)moz_xmalloc(dataLength);
+    memcpy(buffer, aParam.GetCustomImageData(), dataLength);
+    aMsg->WriteBytes(buffer, dataLength);
+    free(buffer);
+  }
+
+  static bool Read(const Message* aMsg, PickleIterator* aIter, paramType* aResult)
+  {
+    NSCursorInfo::Type type;
+    if (!aMsg->ReadInt(aIter, (int*)&type)) {
+      return false;
+    }
+
+    nscoord hotSpotX, hotSpotY;
+    if (!ReadParam(aMsg, aIter, &hotSpotX) ||
+        !ReadParam(aMsg, aIter, &hotSpotY)) {
+      return false;
+    }
+
+    uint32_t dataLength;
+    if (!ReadParam(aMsg, aIter, &dataLength)) {
+      return false;
+    }
+
+    auto data = mozilla::MakeUnique<uint8_t[]>(dataLength);
+    if (dataLength != 0) {
+      if (!aMsg->ReadBytesInto(aIter, data.get(), dataLength)) {
+        return false;
+      }
+    }
+
+    aResult->SetType(type);
+    aResult->SetHotSpot(nsPoint(hotSpotX, hotSpotY));
+    aResult->SetCustomImageData(data.get(), dataLength);
+
+    return true;
+  }
+
+  static void Log(const paramType& aParam, std::wstring* aLog)
+  {
+    const char* typeName = aParam.GetTypeName();
+    nsPoint hotSpot = aParam.GetHotSpot();
+    int hotSpotX, hotSpotY;
+#ifdef NS_COORD_IS_FLOAT
+    hotSpotX = rint(hotSpot.x);
+    hotSpotY = rint(hotSpot.y);
+#else
+    hotSpotX = hotSpot.x;
+    hotSpotY = hotSpot.y;
+#endif
+    uint32_t dataLength = aParam.GetCustomImageDataLength();
+    uint8_t* data = aParam.GetCustomImageData();
+
+    aLog->append(StringPrintf(L"[%s, (%i %i), %u, %p]",
+                              typeName, hotSpotX, hotSpotY, dataLength, data));
+  }
+};
+#else
 template<>
 struct ParamTraits<NSCursorInfo>
 {
@@ -424,6 +589,7 @@ struct ParamTraits<NSCursorInfo>
     return false;
   }
 };
+#endif // #ifdef XP_MACOSX
 
 template <>
 struct ParamTraits<mozilla::plugins::IPCByteRange>
@@ -566,7 +732,9 @@ struct ParamTraits<mozilla::plugins::NPAudioDeviceChangeDetailsIPC>
 // 
 // NB: these guards are based on those where struct NPEvent is defined
 // in npapi.h.  They should be kept in sync.
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+#  include "mozilla/plugins/NPEventOSX.h"
+#elif defined(XP_WIN)
 #  include "mozilla/plugins/NPEventWindows.h"
 #elif defined(XP_UNIX)
 #  include "mozilla/plugins/NPEventUnix.h"
diff --git a/dom/plugins/ipc/PluginModuleChild.cpp b/dom/plugins/ipc/PluginModuleChild.cpp
index bd13b8d9a4..1e65345fda 100644
--- a/dom/plugins/ipc/PluginModuleChild.cpp
+++ b/dom/plugins/ipc/PluginModuleChild.cpp
@@ -132,6 +132,12 @@ PluginModuleChild::PluginModuleChild(bool aIsChrome)
         MOZ_ASSERT(!gChromeInstance);
         gChromeInstance = this;
     }
+
+#ifdef XP_MACOSX
+    if (aIsChrome) {
+      mac_plugin_interposing::child::SetUpCocoaInterposing();
+    }
+#endif
 }
 
 PluginModuleChild::~PluginModuleChild()
@@ -254,8 +260,14 @@ PluginModuleChild::InitForChrome(const std::string& aPluginFilename,
         AddQuirk(QUIRK_FLASH_EXPOSE_COORD_TRANSLATION);
     }
 #endif
+#if defined(XP_MACOSX)
+    const char* namePrefix = "Plugin Content";
+    char nameBuffer[80];
+    SprintfLiteral(nameBuffer, "%s (%s)", namePrefix, info.fName);
+    mozilla::plugins::PluginUtilsOSX::SetProcessName(nameBuffer);
+#endif
     pluginFile.FreePluginInfo(info);
-#if defined(MOZ_X11)
+#if defined(MOZ_X11) || defined(XP_MACOSX)
     if (!mLibrary)
 #endif
     {
diff --git a/dom/plugins/ipc/PluginModuleParent.cpp b/dom/plugins/ipc/PluginModuleParent.cpp
index f7609bcd5e..6ea205ef0f 100755
--- a/dom/plugins/ipc/PluginModuleParent.cpp
+++ b/dom/plugins/ipc/PluginModuleParent.cpp
@@ -1,4 +1,5 @@
 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: sw=4 ts=4 et :
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -47,6 +48,9 @@
 
 #ifdef MOZ_WIDGET_GTK
 #include <glib.h>
+#elif XP_MACOSX
+#include "PluginInterposeOSX.h"
+#include "PluginUtilsOSX.h"
 #endif
 
 using base::KillProcess;
@@ -504,7 +508,7 @@ PluginModuleChromeParent::OnProcessLaunched(const bool aSucceeded)
         if (NS_SUCCEEDED(mAsyncInitRv))
 #endif
         {
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
             mAsyncInitRv = NP_Initialize(mNPNIface,
                                          mNPPIface,
                                          &mAsyncInitError);
@@ -513,6 +517,13 @@ PluginModuleChromeParent::OnProcessLaunched(const bool aSucceeded)
                                          &mAsyncInitError);
 #endif
         }
+
+#if defined(XP_MACOSX)
+        if (NS_SUCCEEDED(mAsyncInitRv)) {
+            mAsyncInitRv = NP_GetEntryPoints(mNPPIface,
+                                             &mAsyncInitError);
+        }
+#endif
     }
 }
 
@@ -1657,8 +1668,13 @@ PluginModuleParent::GetSettings(PluginSettings* aSettings)
     aSettings->supportsWindowless() = GetSetting(NPNVSupportsWindowless);
     aSettings->userAgent() = NullableString(mNPNIface->uagent(nullptr));
 
+#if defined(XP_MACOSX)
+    aSettings->nativeCursorsSupported() =
+      Preferences::GetBool("dom.ipc.plugins.nativeCursorSupport", false);
+#else
     // Need to initialize this to satisfy IPDL.
     aSettings->nativeCursorsSupported() = false;
+#endif
 }
 
 void
@@ -1676,7 +1692,7 @@ PluginModuleChromeParent::CachedSettingChanged(const char* aPref, void* aModule)
     module->CachedSettingChanged();
 }
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
 nsresult
 PluginModuleParent::NP_Initialize(NPNetscapeFuncs* bFuncs, NPPluginFuncs* pFuncs, NPError* error)
 {
@@ -1814,7 +1830,7 @@ PluginModuleParent::NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error)
     return NS_OK;
 }
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
 
 nsresult
 PluginModuleContentParent::NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error)
@@ -1837,10 +1853,20 @@ PluginModuleChromeParent::NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error)
     if (NS_FAILED(rv))
         return rv;
 
+#if defined(XP_MACOSX)
+    if (!mSubprocess->IsConnected()) {
+        // The subprocess isn't connected yet. Defer NP_Initialize until
+        // OnProcessLaunched is invoked.
+        mInitOnAsyncConnect = true;
+        *error = NPERR_NO_ERROR;
+        return NS_OK;
+    }
+#else
     if (mInitOnAsyncConnect) {
         *error = NPERR_NO_ERROR;
         return NS_OK;
     }
+#endif
 
     PluginSettings settings;
     GetSettings(&settings);
@@ -2032,7 +2058,7 @@ PluginModuleParent::NP_GetValue(void *future, NPPVariable aVariable,
     return NS_OK;
 }
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
 nsresult
 PluginModuleParent::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error)
 {
@@ -2041,7 +2067,16 @@ PluginModuleParent::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error)
     *error = NPERR_NO_ERROR;
     if (mIsStartingAsync && !IsChrome()) {
         mNPPIface = pFuncs;
+#if defined(XP_MACOSX)
+        if (mNPInitialized) {
+            SetPluginFuncs(pFuncs);
+            InitAsyncSurrogates();
+        } else {
+            PluginAsyncSurrogate::NP_GetEntryPoints(pFuncs);
+        }
+#else
         PluginAsyncSurrogate::NP_GetEntryPoints(pFuncs);
+#endif
     } else {
         SetPluginFuncs(pFuncs);
     }
@@ -2052,6 +2087,14 @@ PluginModuleParent::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error)
 nsresult
 PluginModuleChromeParent::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error)
 {
+#if defined(XP_MACOSX)
+    if (mInitOnAsyncConnect) {
+        PluginAsyncSurrogate::NP_GetEntryPoints(pFuncs);
+        mNPPIface = pFuncs;
+        *error = NPERR_NO_ERROR;
+        return NS_OK;
+    }
+#else
     if (mIsStartingAsync) {
         PluginAsyncSurrogate::NP_GetEntryPoints(pFuncs);
     }
@@ -2061,6 +2104,7 @@ PluginModuleChromeParent::NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* erro
         *error = NPERR_NO_ERROR;
         return NS_OK;
     }
+#endif
 
     // We need to have the plugin process update its function table here by
     // actually calling NP_GetEntryPoints. The parent's function table will
@@ -2281,7 +2325,18 @@ PluginModuleParent::NPP_GetSitesWithData(nsCOMPtr<nsIGetSitesWithDataCallback> c
     return NS_OK;
 }
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+nsresult
+PluginModuleParent::IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing)
+{
+    PluginInstanceParent* i = PluginInstanceParent::Cast(instance);
+    if (!i)
+        return NS_ERROR_FAILURE;
+
+    return i->IsRemoteDrawingCoreAnimation(aDrawing);
+}
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
 nsresult
 PluginModuleParent::ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor)
 {
@@ -2291,9 +2346,17 @@ PluginModuleParent::ContentsScaleFactorChanged(NPP instance, double aContentsSca
 
     return i->ContentsScaleFactorChanged(aContentsScaleFactor);
 }
-#endif // #if defined(XP_WIN)
+#endif // #if defined(XP_MACOSX)
+
+#if defined(XP_MACOSX)
+bool
+PluginModuleParent::AnswerProcessSomeEvents()
+{
+    mozilla::plugins::PluginUtilsOSX::InvokeNativeEventLoop();
+    return true;
+}
 
-#if !defined(MOZ_WIDGET_GTK)
+#elif !defined(MOZ_WIDGET_GTK)
 bool
 PluginModuleParent::AnswerProcessSomeEvents()
 {
@@ -2351,54 +2414,85 @@ PluginModuleParent::RecvPluginShowWindow(const uint32_t& aWindowId, const bool&
                                          const size_t& aWidth, const size_t& aHeight)
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    CGRect windowBound = ::CGRectMake(aX, aY, aWidth, aHeight);
+    mac_plugin_interposing::parent::OnPluginShowWindow(aWindowId, windowBound, aModal);
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvPluginShowWindow not implemented!");
     return false;
+#endif
 }
 
 bool
 PluginModuleParent::RecvPluginHideWindow(const uint32_t& aWindowId)
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    mac_plugin_interposing::parent::OnPluginHideWindow(aWindowId, OtherPid());
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvPluginHideWindow not implemented!");
     return false;
+#endif
 }
 
 bool
 PluginModuleParent::RecvSetCursor(const NSCursorInfo& aCursorInfo)
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    mac_plugin_interposing::parent::OnSetCursor(aCursorInfo);
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvSetCursor not implemented!");
     return false;
+#endif
 }
 
 bool
 PluginModuleParent::RecvShowCursor(const bool& aShow)
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    mac_plugin_interposing::parent::OnShowCursor(aShow);
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvShowCursor not implemented!");
     return false;
+#endif
 }
 
 bool
 PluginModuleParent::RecvPushCursor(const NSCursorInfo& aCursorInfo)
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    mac_plugin_interposing::parent::OnPushCursor(aCursorInfo);
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvPushCursor not implemented!");
     return false;
+#endif
 }
 
 bool
 PluginModuleParent::RecvPopCursor()
 {
     PLUGIN_LOG_DEBUG(("%s", FULLFUNCTION));
+#if defined(XP_MACOSX)
+    mac_plugin_interposing::parent::OnPopCursor();
+    return true;
+#else
     NS_NOTREACHED(
         "PluginInstanceParent::RecvPopCursor not implemented!");
     return false;
+#endif
 }
 
 bool
diff --git a/dom/plugins/ipc/PluginModuleParent.h b/dom/plugins/ipc/PluginModuleParent.h
index 11c2a47c65..909e8fe351 100644
--- a/dom/plugins/ipc/PluginModuleParent.h
+++ b/dom/plugins/ipc/PluginModuleParent.h
@@ -247,7 +247,7 @@ protected:
                        const mozilla::NativeEventData& aNativeKeyData,
                        bool aIsConsumed) override;
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
     virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPPluginFuncs* pFuncs, NPError* error) override;
 #else
     virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error) override;
@@ -257,7 +257,7 @@ protected:
     virtual nsresult NP_GetMIMEDescription(const char** mimeDesc) override;
     virtual nsresult NP_GetValue(void *future, NPPVariable aVariable,
                                  void *aValue, NPError* error) override;
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
     virtual nsresult NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error) override;
 #endif
     virtual nsresult NPP_New(NPMIMEType pluginType, NPP instance,
@@ -278,7 +278,10 @@ private:
 
 public:
 
-#if defined(XP_WIN)
+#if defined(XP_MACOSX)
+    virtual nsresult IsRemoteDrawingCoreAnimation(NPP instance, bool *aDrawing) override;
+#endif
+#if defined(XP_MACOSX) || defined(XP_WIN)
     virtual nsresult ContentsScaleFactorChanged(NPP instance, double aContentsScaleFactor) override;
 #endif
 
@@ -352,7 +355,7 @@ class PluginModuleContentParent : public PluginModuleParent
 
     virtual ~PluginModuleContentParent();
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
     nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error) override;
 #endif
 
@@ -476,13 +479,13 @@ private:
     PluginProcessParent* Process() const { return mSubprocess; }
     base::ProcessHandle ChildProcessHandle() { return mSubprocess->GetChildProcessHandle(); }
 
-#if defined(XP_UNIX)
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
     virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPPluginFuncs* pFuncs, NPError* error) override;
 #else
     virtual nsresult NP_Initialize(NPNetscapeFuncs* bFuncs, NPError* error) override;
 #endif
 
-#if defined(XP_WIN)
+#if defined(XP_WIN) || defined(XP_MACOSX)
     virtual nsresult NP_GetEntryPoints(NPPluginFuncs* pFuncs, NPError* error) override;
 #endif
 
diff --git a/dom/plugins/ipc/PluginProcessChild.cpp b/dom/plugins/ipc/PluginProcessChild.cpp
index 9ba0926636..32bf062150 100644
--- a/dom/plugins/ipc/PluginProcessChild.cpp
+++ b/dom/plugins/ipc/PluginProcessChild.cpp
@@ -1,4 +1,5 @@
 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: sw=4 ts=4 et :
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
@@ -12,6 +13,13 @@
 #include "base/string_util.h"
 #include "nsDebugImpl.h"
 
+#if defined(XP_MACOSX)
+#include "nsCocoaFeatures.h"
+// An undocumented CoreGraphics framework method, present in the same form
+// since at least OS X 10.5.
+extern "C" CGError CGSSetDebugOptions(int options);
+#endif
+
 #ifdef XP_WIN
 bool ShouldProtectPluginCurrentDirectory(char16ptr_t pluginFilePath);
 #endif
@@ -32,6 +40,42 @@ PluginProcessChild::Init()
 {
     nsDebugImpl::SetMultiprocessMode("NPAPI");
 
+#if defined(XP_MACOSX)
+    // Remove the trigger for "dyld interposing" that we added in
+    // GeckoChildProcessHost::PerformAsyncLaunchInternal(), in the host
+    // process just before we were launched.  Dyld interposing will still
+    // happen in our process (the plugin child process).  But we don't want
+    // it to happen in any processes that the plugin might launch from our
+    // process.
+    nsCString interpose(PR_GetEnv("DYLD_INSERT_LIBRARIES"));
+    if (!interpose.IsEmpty()) {
+        // If we added the path to libplugin_child_interpose.dylib to an
+        // existing DYLD_INSERT_LIBRARIES, we appended it to the end, after a
+        // ":" path seperator.
+        int32_t lastSeparatorPos = interpose.RFind(":");
+        int32_t lastTriggerPos = interpose.RFind("libplugin_child_interpose.dylib");
+        bool needsReset = false;
+        if (lastTriggerPos != -1) {
+            if (lastSeparatorPos == -1) {
+                interpose.Truncate();
+                needsReset = true;
+            } else if (lastTriggerPos > lastSeparatorPos) {
+                interpose.SetLength(lastSeparatorPos);
+                needsReset = true;
+            }
+        }
+        if (needsReset) {
+            nsCString setInterpose("DYLD_INSERT_LIBRARIES=");
+            if (!interpose.IsEmpty()) {
+                setInterpose.Append(interpose);
+            }
+            // Values passed to PR_SetEnv() must be seperately allocated.
+            char* setInterposePtr = strdup(setInterpose.get());
+            PR_SetEnv(setInterposePtr);
+        }
+    }
+#endif
+
     // Certain plugins, such as flash, steal the unhandled exception filter
     // thus we never get crash reports when they fault. This call fixes it.
     message_loop()->set_exception_restoration(true);
@@ -71,6 +115,17 @@ PluginProcessChild::Init()
     bool retval = mPlugin.InitForChrome(pluginFilename, ParentPid(),
                                         IOThreadChild::message_loop(),
                                         IOThreadChild::channel());
+#if defined(XP_MACOSX)
+    if (nsCocoaFeatures::OnYosemiteOrLater()) {
+      // Explicitly turn off CGEvent logging.  This works around bug 1092855.
+      // If there are already CGEvents in the log, turning off logging also
+      // causes those events to be written to disk.  But at this point no
+      // CGEvents have yet been processed.  CGEvents are events (usually
+      // input events) pulled from the WindowServer.  An option of 0x80000008
+      // turns on CGEvent logging.
+      CGSSetDebugOptions(0x80000007);
+    }
+#endif
     return retval;
 }
 
diff --git a/dom/plugins/ipc/PluginProcessParent.cpp b/dom/plugins/ipc/PluginProcessParent.cpp
index 4445681359..53cd78ff3b 100644
--- a/dom/plugins/ipc/PluginProcessParent.cpp
+++ b/dom/plugins/ipc/PluginProcessParent.cpp
@@ -47,6 +47,13 @@ PluginProcessParent::Launch(mozilla::UniquePtr<LaunchCompleteTask> aLaunchComple
     uint32_t containerArchitectures = GetSupportedArchitecturesForProcessType(GeckoProcessType_Plugin);
 
     uint32_t pluginLibArchitectures = currentArchitecture;
+#ifdef XP_MACOSX
+    nsresult rv = GetArchitecturesForBinary(mPluginFilePath.c_str(), &pluginLibArchitectures);
+    if (NS_FAILED(rv)) {
+        // If the call failed just assume that we want the current architecture.
+        pluginLibArchitectures = currentArchitecture;
+    }
+#endif
 
     ProcessArchitecture selectedArchitecture = currentArchitecture;
     if (!(pluginLibArchitectures & containerArchitectures & currentArchitecture)) {
diff --git a/dom/plugins/ipc/PluginQuirks.cpp b/dom/plugins/ipc/PluginQuirks.cpp
index a8b0f62056..c60cf88362 100644
--- a/dom/plugins/ipc/PluginQuirks.cpp
+++ b/dom/plugins/ipc/PluginQuirks.cpp
@@ -49,6 +49,16 @@ int GetQuirksFromMimeTypeAndFilename(const nsCString& aMimeType,
     }
 #endif
 
+#ifdef XP_MACOSX
+    // Whitelist Flash and Quicktime to support offline renderer
+    NS_NAMED_LITERAL_CSTRING(quicktime, "QuickTime Plugin.plugin");
+    if (specialType == nsPluginHost::eSpecialType_Flash) {
+        quirks |= QUIRK_ALLOW_OFFLINE_RENDERER;
+    } else if (FindInReadable(quicktime, aPluginFilename)) {
+        quirks |= QUIRK_ALLOW_OFFLINE_RENDERER;
+    }
+#endif
+
 #ifdef OS_WIN
     if (specialType == nsPluginHost::eSpecialType_Unity) {
         quirks |= QUIRK_UNITY_FIXUP_MOUSE_CAPTURE;
diff --git a/dom/plugins/ipc/PluginUtilsOSX.h b/dom/plugins/ipc/PluginUtilsOSX.h
new file mode 100644
index 0000000000..c201782c0f
--- /dev/null
+++ b/dom/plugins/ipc/PluginUtilsOSX.h
@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+// vim:set ts=2 sts=2 sw=2 et cin:
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef dom_plugins_PluginUtilsOSX_h
+#define dom_plugins_PluginUtilsOSX_h 1
+
+#include "npapi.h"
+#include "mozilla/gfx/QuartzSupport.h"
+#include "nsRect.h"
+
+namespace mozilla {
+namespace plugins {
+namespace PluginUtilsOSX {
+
+// Need to call back into the browser's message loop to process event.
+typedef void (*RemoteProcessEvents) (void*);
+
+NPError ShowCocoaContextMenu(void* aMenu, int aX, int aY, void* pluginModule, RemoteProcessEvents remoteEvent);
+
+void InvokeNativeEventLoop();
+
+// Need to call back and send a cocoa draw event to the plugin.
+typedef void (*DrawPluginFunc) (CGContextRef, void*, nsIntRect aUpdateRect);
+
+void* GetCGLayer(DrawPluginFunc aFunc, void* aPluginInstance, double aContentsScaleFactor);
+void ReleaseCGLayer(void* cgLayer);
+void Repaint(void* cgLayer, nsIntRect aRect);
+
+bool SetProcessName(const char* aProcessName);
+
+/*
+ * Provides a wrapper around nsCARenderer to manage double buffering
+ * without having to unbind nsCARenderer on every surface swaps.
+ *
+ * The double buffer renderer begins with no initialize surfaces.
+ * The buffers can be initialized and cleared individually.
+ * Swapping still occurs regardless if the buffers are initialized.
+ */
+class nsDoubleBufferCARenderer {
+public:
+  nsDoubleBufferCARenderer() : mCALayer(nullptr), mContentsScaleFactor(1.0) {}
+  // Returns width in "display pixels".  A "display pixel" is the smallest
+  // fully addressable part of a display.  But in HiDPI modes each "display
+  // pixel" corresponds to more than one device pixel.  Multiply display pixels
+  // by mContentsScaleFactor to get device pixels.
+  size_t GetFrontSurfaceWidth();
+  // Returns height in "display pixels".  Multiply by
+  // mContentsScaleFactor to get device pixels.
+  size_t GetFrontSurfaceHeight();
+  double GetFrontSurfaceContentsScaleFactor();
+  // Returns width in "display pixels".  Multiply by
+  // mContentsScaleFactor to get device pixels.
+  size_t GetBackSurfaceWidth();
+  // Returns height in "display pixels".  Multiply by
+  // mContentsScaleFactor to get device pixels.
+  size_t GetBackSurfaceHeight();
+  double GetBackSurfaceContentsScaleFactor();
+  IOSurfaceID GetFrontSurfaceID();
+
+  bool HasBackSurface();
+  bool HasFrontSurface();
+  bool HasCALayer();
+
+  void SetCALayer(void *aCALayer);
+  // aWidth and aHeight are in "display pixels".  Multiply by
+  // aContentsScaleFactor to get device pixels.
+  bool InitFrontSurface(size_t aWidth, size_t aHeight,
+                        double aContentsScaleFactor,
+                        AllowOfflineRendererEnum aAllowOfflineRenderer);
+  void Render();
+  void SwapSurfaces();
+  void ClearFrontSurface();
+  void ClearBackSurface();
+
+  double GetContentsScaleFactor() { return mContentsScaleFactor; }
+
+private:
+  void *mCALayer;
+  RefPtr<nsCARenderer> mCARenderer;
+  RefPtr<MacIOSurface> mFrontSurface;
+  RefPtr<MacIOSurface> mBackSurface;
+  double mContentsScaleFactor;
+};
+
+} // namespace PluginUtilsOSX
+} // namespace plugins
+} // namespace mozilla
+
+#endif //dom_plugins_PluginUtilsOSX_h
diff --git a/dom/plugins/ipc/PluginUtilsOSX.mm b/dom/plugins/ipc/PluginUtilsOSX.mm
new file mode 100644
index 0000000000..2a920f7f61
--- /dev/null
+++ b/dom/plugins/ipc/PluginUtilsOSX.mm
@@ -0,0 +1,462 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+// vim:set ts=2 sts=2 sw=2 et cin:
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include <dlfcn.h>
+#import <AppKit/AppKit.h>
+#import <QuartzCore/QuartzCore.h>
+#include "PluginUtilsOSX.h"
+
+// Remove definitions for try/catch interfering with ObjCException macros.
+#include "nsObjCExceptions.h"
+#include "nsCocoaUtils.h"
+
+#include "nsDebug.h"
+
+#include "mozilla/Sprintf.h"
+
+@interface CALayer (ContentsScale)
+- (double)contentsScale;
+- (void)setContentsScale:(double)scale;
+@end
+
+using namespace mozilla::plugins::PluginUtilsOSX;
+
+@interface CGBridgeLayer : CALayer {
+  DrawPluginFunc mDrawFunc;
+  void* mPluginInstance;
+  nsIntRect mUpdateRect;
+}
+- (void)setDrawFunc:(DrawPluginFunc)aFunc
+     pluginInstance:(void*)aPluginInstance;
+- (void)updateRect:(nsIntRect)aRect;
+
+@end
+
+// CGBitmapContextSetData() is an undocumented function present (with
+// the same signature) since at least OS X 10.5.  As the name suggests,
+// it's used to replace the "data" in a bitmap context that was
+// originally specified in a call to CGBitmapContextCreate() or
+// CGBitmapContextCreateWithData().
+typedef void (*CGBitmapContextSetDataFunc) (CGContextRef c,
+                                            size_t x,
+                                            size_t y,
+                                            size_t width,
+                                            size_t height,
+                                            void* data,
+                                            size_t bitsPerComponent,
+                                            size_t bitsPerPixel,
+                                            size_t bytesPerRow);
+CGBitmapContextSetDataFunc CGBitmapContextSetDataPtr = NULL;
+
+@implementation CGBridgeLayer
+- (void) updateRect:(nsIntRect)aRect
+{
+   mUpdateRect.UnionRect(mUpdateRect, aRect);
+}
+
+- (void) setDrawFunc:(DrawPluginFunc)aFunc
+      pluginInstance:(void*)aPluginInstance
+{
+  mDrawFunc = aFunc;
+  mPluginInstance = aPluginInstance;
+}
+
+- (void)drawInContext:(CGContextRef)aCGContext
+{
+  ::CGContextSaveGState(aCGContext); 
+  ::CGContextTranslateCTM(aCGContext, 0, self.bounds.size.height);
+  ::CGContextScaleCTM(aCGContext, (CGFloat) 1, (CGFloat) -1);
+
+  mUpdateRect = nsIntRect::Truncate(0, 0, self.bounds.size.width, self.bounds.size.height);
+
+  mDrawFunc(aCGContext, mPluginInstance, mUpdateRect);
+
+  ::CGContextRestoreGState(aCGContext);
+
+  mUpdateRect.SetEmpty();
+}
+
+@end
+
+void* mozilla::plugins::PluginUtilsOSX::GetCGLayer(DrawPluginFunc aFunc, 
+                                                   void* aPluginInstance, 
+                                                   double aContentsScaleFactor) {
+  CGBridgeLayer *bridgeLayer = [[CGBridgeLayer alloc] init];
+
+  // We need to make bridgeLayer behave properly when its superlayer changes
+  // size (in nsCARenderer::SetBounds()).
+  bridgeLayer.autoresizingMask = kCALayerWidthSizable | kCALayerHeightSizable;
+  bridgeLayer.needsDisplayOnBoundsChange = YES;
+  NSNull *nullValue = [NSNull null];
+  NSDictionary *actions = [NSDictionary dictionaryWithObjectsAndKeys:
+                             nullValue, @"bounds",
+                             nullValue, @"contents",
+                             nullValue, @"contentsRect",
+                             nullValue, @"position",
+                             nil];
+  [bridgeLayer setStyle:[NSDictionary dictionaryWithObject:actions forKey:@"actions"]];
+
+  // For reasons that aren't clear (perhaps one or more OS bugs), we can only
+  // use full HiDPI resolution here if the tree is built with the 10.7 SDK or
+  // up.  If we build with the 10.6 SDK, changing the contentsScale property
+  // of bridgeLayer (even to the same value) causes it to stop working (go
+  // blank).  This doesn't happen with objects that are members of the CALayer
+  // class (as opposed to one of its subclasses).
+#if defined(MAC_OS_X_VERSION_10_7) && \
+    MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_7
+  if ([bridgeLayer respondsToSelector:@selector(setContentsScale:)]) {
+    bridgeLayer.contentsScale = aContentsScaleFactor;
+  }
+#endif
+
+  [bridgeLayer setDrawFunc:aFunc
+            pluginInstance:aPluginInstance];
+  return bridgeLayer;
+}
+
+void mozilla::plugins::PluginUtilsOSX::ReleaseCGLayer(void *cgLayer) {
+  CGBridgeLayer *bridgeLayer = (CGBridgeLayer*)cgLayer;
+  [bridgeLayer release];
+}
+
+void mozilla::plugins::PluginUtilsOSX::Repaint(void *caLayer, nsIntRect aRect) {
+  CGBridgeLayer *bridgeLayer = (CGBridgeLayer*)caLayer;
+  [CATransaction begin];
+  [bridgeLayer updateRect:aRect];
+  [bridgeLayer setNeedsDisplay];
+  [bridgeLayer displayIfNeeded];
+  [CATransaction commit];
+}
+
+@interface EventProcessor : NSObject {
+  RemoteProcessEvents   aRemoteEvents;
+  void                 *aPluginModule;
+}
+- (void)setRemoteEvents:(RemoteProcessEvents) remoteEvents pluginModule:(void*) pluginModule;
+- (void)onTick;
+@end
+
+@implementation EventProcessor
+- (void) onTick
+{
+    aRemoteEvents(aPluginModule);
+}
+
+- (void)setRemoteEvents:(RemoteProcessEvents) remoteEvents pluginModule:(void*) pluginModule
+{
+    aRemoteEvents = remoteEvents;
+    aPluginModule = pluginModule;
+}
+@end
+
+#define EVENT_PROCESS_DELAY 0.05 // 50 ms
+
+NPError mozilla::plugins::PluginUtilsOSX::ShowCocoaContextMenu(void* aMenu, int aX, int aY, void* pluginModule, RemoteProcessEvents remoteEvent) 
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  // Set the native cursor to the OS default (an arrow) before displaying the
+  // context menu.  Otherwise (if the plugin has changed the cursor) it may
+  // stay as the plugin has set it -- which means it may be invisible.  We
+  // need to do this because we display the context menu without making the
+  // plugin process the foreground process.  If we did, the cursor would
+  // change to an arrow cursor automatically -- as it does in Chrome.
+  [[NSCursor arrowCursor] set];
+
+  EventProcessor* eventProcessor = nullptr;
+  NSTimer *eventTimer = nullptr;
+  if (pluginModule) {
+    // Create a timer to process browser events while waiting
+    // on the menu. This prevents the browser from hanging
+    // during the lifetime of the menu.
+    eventProcessor = [[EventProcessor alloc] init];
+    [eventProcessor setRemoteEvents:remoteEvent pluginModule:pluginModule];
+    eventTimer = [NSTimer timerWithTimeInterval:EVENT_PROCESS_DELAY
+                                   target:eventProcessor selector:@selector(onTick)
+                                   userInfo:nil repeats:TRUE];
+    // Use NSEventTrackingRunLoopMode otherwise the timer will
+    // not fire during the right click menu.
+    [[NSRunLoop currentRunLoop] addTimer:eventTimer
+                                 forMode:NSEventTrackingRunLoopMode];
+  }
+
+  NSMenu* nsmenu = reinterpret_cast<NSMenu*>(aMenu);
+  NSPoint screen_point = ::NSMakePoint(aX, aY);
+
+  [nsmenu popUpMenuPositioningItem:nil atLocation:screen_point inView:nil];
+
+  if (pluginModule) {
+    [eventTimer invalidate];
+    [eventProcessor release];
+  }
+
+  return NPERR_NO_ERROR;
+
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(NPERR_GENERIC_ERROR);
+}
+
+void mozilla::plugins::PluginUtilsOSX::InvokeNativeEventLoop()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+  ::CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.0, true);
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
+
+#define UNDOCUMENTED_SESSION_CONSTANT ((int)-2)
+namespace mozilla {
+namespace plugins {
+namespace PluginUtilsOSX {
+  static void *sApplicationASN = NULL;
+  static void *sApplicationInfoItem = NULL;
+} // namespace PluginUtilsOSX
+} // namespace plugins
+} // namespace mozilla
+
+bool mozilla::plugins::PluginUtilsOSX::SetProcessName(const char* aProcessName) {
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+  nsAutoreleasePool localPool;
+
+  if (!aProcessName || strcmp(aProcessName, "") == 0) {
+    return false;
+  }
+
+  NSString *currentName = [[[NSBundle mainBundle] localizedInfoDictionary]
+                              objectForKey:(NSString *)kCFBundleNameKey];
+
+  char formattedName[1024];
+  SprintfLiteral(formattedName, "%s %s", [currentName UTF8String], aProcessName);
+
+  aProcessName = formattedName;
+
+  // This function is based on Chrome/Webkit's and relies on potentially dangerous SPI.
+  typedef CFTypeRef (*LSGetASNType)();
+  typedef OSStatus (*LSSetInformationItemType)(int, CFTypeRef,
+                                               CFStringRef, 
+                                               CFStringRef,
+                                               CFDictionaryRef*);
+
+  CFBundleRef launchServices = ::CFBundleGetBundleWithIdentifier(
+                                          CFSTR("com.apple.LaunchServices"));
+  if (!launchServices) {
+    NS_WARNING("Failed to set process name: Could not open LaunchServices bundle");
+    return false;
+  }
+
+  if (!sApplicationASN) {
+    sApplicationASN = ::CFBundleGetFunctionPointerForName(launchServices, 
+                                            CFSTR("_LSGetCurrentApplicationASN"));
+  }
+
+  LSGetASNType getASNFunc = reinterpret_cast<LSGetASNType>
+                                          (sApplicationASN);
+
+  if (!sApplicationInfoItem) {
+    sApplicationInfoItem = ::CFBundleGetFunctionPointerForName(launchServices, 
+                                            CFSTR("_LSSetApplicationInformationItem"));
+  }
+
+  LSSetInformationItemType setInformationItemFunc 
+                                          = reinterpret_cast<LSSetInformationItemType>
+                                          (sApplicationInfoItem);
+
+  void * displayNameKeyAddr = ::CFBundleGetDataPointerForName(launchServices,
+                                          CFSTR("_kLSDisplayNameKey"));
+
+  CFStringRef displayNameKey = nil;
+  if (displayNameKeyAddr) {
+    displayNameKey = reinterpret_cast<CFStringRef>(*(CFStringRef*)displayNameKeyAddr);
+  }
+
+  // Rename will fail without this
+  ProcessSerialNumber psn;
+  if (::GetCurrentProcess(&psn) != noErr) {
+    return false;
+  }
+
+  CFTypeRef currentAsn = getASNFunc();
+
+  if (!getASNFunc || !setInformationItemFunc || 
+      !displayNameKey || !currentAsn) {
+    NS_WARNING("Failed to set process name: Accessing launchServices failed");
+    return false;
+  }
+
+  CFStringRef processName = ::CFStringCreateWithCString(nil, 
+                                                        aProcessName, 
+                                                        kCFStringEncodingASCII);
+  if (!processName) {
+    NS_WARNING("Failed to set process name: Could not create CFStringRef");
+    return false;
+  }
+
+  OSErr err = setInformationItemFunc(UNDOCUMENTED_SESSION_CONSTANT, currentAsn,
+                                     displayNameKey, processName,
+                                     nil); // Optional out param
+  ::CFRelease(processName);
+  if (err != noErr) {
+    NS_WARNING("Failed to set process name: LSSetInformationItemType err");
+    return false;
+  }
+
+  return true;
+  NS_OBJC_END_TRY_ABORT_BLOCK_RETURN(false);
+}
+
+namespace mozilla {
+namespace plugins {
+namespace PluginUtilsOSX {
+
+size_t nsDoubleBufferCARenderer::GetFrontSurfaceWidth() {
+  if (!HasFrontSurface()) {
+    return 0;
+  }
+
+  return mFrontSurface->GetWidth();
+}
+
+size_t nsDoubleBufferCARenderer::GetFrontSurfaceHeight() {
+  if (!HasFrontSurface()) {
+    return 0;
+  }
+
+  return mFrontSurface->GetHeight();
+}
+
+double nsDoubleBufferCARenderer::GetFrontSurfaceContentsScaleFactor() {
+  if (!HasFrontSurface()) {
+    return 1.0;
+  }
+
+  return mFrontSurface->GetContentsScaleFactor();
+}
+
+size_t nsDoubleBufferCARenderer::GetBackSurfaceWidth() {
+  if (!HasBackSurface()) {
+    return 0;
+  }
+
+  return mBackSurface->GetWidth();
+}
+
+size_t nsDoubleBufferCARenderer::GetBackSurfaceHeight() {
+  if (!HasBackSurface()) {
+    return 0;
+  }
+
+  return mBackSurface->GetHeight();
+}
+
+double nsDoubleBufferCARenderer::GetBackSurfaceContentsScaleFactor() {
+  if (!HasBackSurface()) {
+    return 1.0;
+  }
+
+  return mBackSurface->GetContentsScaleFactor();
+}
+
+IOSurfaceID nsDoubleBufferCARenderer::GetFrontSurfaceID() {
+  if (!HasFrontSurface()) {
+    return 0;
+  }
+
+  return mFrontSurface->GetIOSurfaceID();
+}
+
+bool nsDoubleBufferCARenderer::HasBackSurface() {
+  return !!mBackSurface;
+}
+
+bool nsDoubleBufferCARenderer::HasFrontSurface() {
+  return !!mFrontSurface;
+}
+
+bool nsDoubleBufferCARenderer::HasCALayer() {
+  return !!mCALayer;
+}
+
+void nsDoubleBufferCARenderer::SetCALayer(void *aCALayer) {
+  mCALayer = aCALayer;
+}
+
+bool nsDoubleBufferCARenderer::InitFrontSurface(size_t aWidth, size_t aHeight,
+                                                double aContentsScaleFactor,
+                                                AllowOfflineRendererEnum aAllowOfflineRenderer) {
+  if (!mCALayer) {
+    return false;
+  }
+
+  mContentsScaleFactor = aContentsScaleFactor;
+  mFrontSurface = MacIOSurface::CreateIOSurface(aWidth, aHeight, mContentsScaleFactor);
+  if (!mFrontSurface) {
+    mCARenderer = nullptr;
+    return false;
+  }
+
+  if (!mCARenderer) {
+    mCARenderer = new nsCARenderer();
+    if (!mCARenderer) {
+      mFrontSurface = nullptr;
+      return false;
+    }
+
+    mCARenderer->AttachIOSurface(mFrontSurface);
+
+    nsresult result = mCARenderer->SetupRenderer(mCALayer,
+                        mFrontSurface->GetWidth(),
+                        mFrontSurface->GetHeight(),
+                        mContentsScaleFactor,
+                        aAllowOfflineRenderer);
+
+    if (result != NS_OK) {
+      mCARenderer = nullptr;
+      mFrontSurface = nullptr;
+      return false;
+    }
+  } else {
+    mCARenderer->AttachIOSurface(mFrontSurface);
+  }
+
+  return true;
+}
+
+void nsDoubleBufferCARenderer::Render() {
+  if (!HasFrontSurface() || !mCARenderer) {
+    return;
+  }
+
+  mCARenderer->Render(GetFrontSurfaceWidth(), GetFrontSurfaceHeight(),
+                      mContentsScaleFactor, nullptr);
+}
+
+void nsDoubleBufferCARenderer::SwapSurfaces() {
+  RefPtr<MacIOSurface> prevFrontSurface = mFrontSurface;
+  mFrontSurface = mBackSurface;
+  mBackSurface = prevFrontSurface;
+
+  if (mFrontSurface) {
+    mCARenderer->AttachIOSurface(mFrontSurface);
+  }
+}
+
+void nsDoubleBufferCARenderer::ClearFrontSurface() {
+  mFrontSurface = nullptr;
+  if (!mFrontSurface && !mBackSurface) {
+    mCARenderer = nullptr;
+  }
+}
+
+void nsDoubleBufferCARenderer::ClearBackSurface() {
+  mBackSurface = nullptr;
+  if (!mFrontSurface && !mBackSurface) {
+    mCARenderer = nullptr;
+  }
+}
+
+} // namespace PluginUtilsOSX
+} // namespace plugins
+} // namespace mozilla
+
diff --git a/dom/plugins/ipc/interpose/moz.build b/dom/plugins/ipc/interpose/moz.build
new file mode 100644
index 0000000000..319c325a70
--- /dev/null
+++ b/dom/plugins/ipc/interpose/moz.build
@@ -0,0 +1,12 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+SharedLibrary('plugin_child_interpose')
+
+SOURCES += [ "%s.mm" % (LIBRARY_NAME) ]
+
+OS_LIBS += ['-framework Carbon']
+
+DIST_INSTALL = True
diff --git a/dom/plugins/ipc/interpose/plugin_child_interpose.mm b/dom/plugins/ipc/interpose/plugin_child_interpose.mm
new file mode 100644
index 0000000000..58c39b0a1c
--- /dev/null
+++ b/dom/plugins/ipc/interpose/plugin_child_interpose.mm
@@ -0,0 +1,134 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Use "dyld interposing" to hook methods imported from other libraries in the
+// plugin child process.  The basic technique is described at
+// http://books.google.com/books?id=K8vUkpOXhN4C&pg=PA73&lpg=PA73&dq=__interpose&source=bl&ots=OJnnXZYpZC&sig=o7I3lXvoduUi13SrPfOON7o3do4&hl=en&ei=AoehS9brCYGQNrvsmeUM&sa=X&oi=book_result&ct=result&resnum=6&ved=0CBsQ6AEwBQ#v=onepage&q=__interpose&f=false.
+// The idea of doing it for the plugin child process comes from Chromium code,
+// particularly from plugin_carbon_interpose_mac.cc
+// (http://codesearch.google.com/codesearch/p?hl=en#OAMlx_jo-ck/src/chrome/browser/plugin_carbon_interpose_mac.cc&q=nscursor&exact_package=chromium&d=1&l=168)
+// and from PluginProcessHost::Init() in plugin_process_host.cc
+// (http://codesearch.google.com/codesearch/p?hl=en#OAMlx_jo-ck/src/content/browser/plugin_process_host.cc&q=nscursor&exact_package=chromium&d=1&l=222).
+
+// These hooks are needed to make certain OS calls work from the child process
+// (a background process) that would normally only work when called in the
+// parent process (the foreground process).  They allow us to serialize
+// information from the child process to the parent process, so that the same
+// (or equivalent) calls can be made from the parent process.
+
+// This file lives in a seperate module (libplugin_child_interpose.dylib),
+// which will get loaded by the OS before any other modules when the plugin
+// child process is launched (from GeckoChildProcessHost::
+// PerformAsyncLaunchInternal()).  For this reason it shouldn't link in other
+// browser modules when loaded.  Instead it should use dlsym() to load
+// pointers to the methods it wants to call in other modules.
+
+#if !defined(__LP64__)
+
+#include <dlfcn.h>
+#import <Carbon/Carbon.h>
+
+// The header file QuickdrawAPI.h is missing on OS X 10.7 and up (though the
+// QuickDraw APIs defined in it are still present) -- so we need to supply the
+// relevant parts of its contents here.  It's likely that Apple will eventually
+// remove the APIs themselves (probably in OS X 10.8), so we need to make them
+// weak imports, and test for their presence before using them.
+#if !defined(__QUICKDRAWAPI__)
+
+struct Cursor;
+extern "C" void SetCursor(const Cursor * crsr) __attribute__((weak_import));
+
+#endif /* __QUICKDRAWAPI__ */
+
+BOOL (*OnSetThemeCursorPtr) (ThemeCursor) = NULL;
+BOOL (*OnSetCursorPtr) (const Cursor*) = NULL;
+BOOL (*OnHideCursorPtr) () = NULL;
+BOOL (*OnShowCursorPtr) () = NULL;
+
+static BOOL loadXULPtrs()
+{
+  if (!OnSetThemeCursorPtr) {
+    // mac_plugin_interposing_child_OnSetThemeCursor(ThemeCursor cursor) is in
+    // PluginInterposeOSX.mm
+    OnSetThemeCursorPtr = (BOOL(*)(ThemeCursor))
+      dlsym(RTLD_DEFAULT, "mac_plugin_interposing_child_OnSetThemeCursor");
+  }
+  if (!OnSetCursorPtr) {
+    // mac_plugin_interposing_child_OnSetCursor(const Cursor* cursor) is in
+    // PluginInterposeOSX.mm
+    OnSetCursorPtr = (BOOL(*)(const Cursor*))
+      dlsym(RTLD_DEFAULT, "mac_plugin_interposing_child_OnSetCursor");
+  }
+  if (!OnHideCursorPtr) {
+    // mac_plugin_interposing_child_OnHideCursor() is in PluginInterposeOSX.mm
+    OnHideCursorPtr = (BOOL(*)())
+      dlsym(RTLD_DEFAULT, "mac_plugin_interposing_child_OnHideCursor");
+  }
+  if (!OnShowCursorPtr) {
+    // mac_plugin_interposing_child_OnShowCursor() is in PluginInterposeOSX.mm
+    OnShowCursorPtr = (BOOL(*)())
+      dlsym(RTLD_DEFAULT, "mac_plugin_interposing_child_OnShowCursor");
+  }
+  return (OnSetCursorPtr && OnSetThemeCursorPtr && OnHideCursorPtr && OnShowCursorPtr);
+}
+
+static OSStatus MacPluginChildSetThemeCursor(ThemeCursor cursor)
+{
+  if (loadXULPtrs()) {
+    OnSetThemeCursorPtr(cursor);
+  }
+  return ::SetThemeCursor(cursor);
+}
+
+static void MacPluginChildSetCursor(const Cursor* cursor)
+{
+  if (::SetCursor) {
+    if (loadXULPtrs()) {
+      OnSetCursorPtr(cursor);
+    }
+    ::SetCursor(cursor);
+  }
+}
+
+static CGError MacPluginChildCGDisplayHideCursor(CGDirectDisplayID display)
+{
+  if (loadXULPtrs()) {
+    OnHideCursorPtr();
+  }
+  return ::CGDisplayHideCursor(display);
+}
+
+static CGError MacPluginChildCGDisplayShowCursor(CGDirectDisplayID display)
+{
+  if (loadXULPtrs()) {
+    OnShowCursorPtr();
+  }
+  return ::CGDisplayShowCursor(display);
+}
+
+#pragma mark -
+
+struct interpose_substitution {
+  const void* replacement;
+  const void* original;
+};
+
+#define INTERPOSE_FUNCTION(function) \
+    { reinterpret_cast<const void*>(MacPluginChild##function), \
+      reinterpret_cast<const void*>(function) }
+
+__attribute__((used)) static const interpose_substitution substitutions[]
+    __attribute__((section("__DATA, __interpose"))) = {
+  INTERPOSE_FUNCTION(SetThemeCursor),
+  INTERPOSE_FUNCTION(CGDisplayHideCursor),
+  INTERPOSE_FUNCTION(CGDisplayShowCursor),
+  // SetCursor() and other QuickDraw APIs will probably be removed in OS X
+  // 10.8.  But this will make 'SetCursor' NULL, which will just stop the OS
+  // from interposing it (tested using an INTERPOSE_FUNCTION_BROKEN macro
+  // that just sets the second address of each tuple to NULL).
+  INTERPOSE_FUNCTION(SetCursor),
+};
+
+#endif  // !__LP64__
diff --git a/dom/plugins/ipc/moz.build b/dom/plugins/ipc/moz.build
index 00f9a47128..9190d19272 100644
--- a/dom/plugins/ipc/moz.build
+++ b/dom/plugins/ipc/moz.build
@@ -3,6 +3,9 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
+    DIRS += ['interpose']
+
 EXPORTS.mozilla += [
     'PluginLibrary.h',
 ]
@@ -13,6 +16,7 @@ EXPORTS.mozilla.plugins += [
     'BrowserStreamParent.h',
     'ChildAsyncCall.h',
     'ChildTimer.h',
+    'NPEventOSX.h',
     'NPEventUnix.h',
     'NPEventWindows.h',
     'PluginAsyncSurrogate.h',
@@ -32,6 +36,7 @@ EXPORTS.mozilla.plugins += [
     'PluginScriptableObjectUtils.h',
     'PluginStreamChild.h',
     'PluginStreamParent.h',
+    'PluginUtilsOSX.h',
     'PluginWidgetChild.h',
     'PluginWidgetParent.h',
     'StreamNotifyChild.h',
@@ -53,6 +58,11 @@ if CONFIG['OS_ARCH'] == 'WINNT':
         'hangui',
     ]
 
+if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
+    EXPORTS.mozilla.plugins += [
+        'PluginInterposeOSX.h',
+    ]
+
 SOURCES += [
     'BrowserStreamChild.cpp',
     'BrowserStreamParent.cpp',
@@ -76,6 +86,12 @@ SOURCES += [
     'PluginWidgetParent.cpp',
 ]
 
+if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
+    SOURCES += [
+        'PluginInterposeOSX.mm',
+        'PluginUtilsOSX.mm',
+    ]
+
 if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'windows':
     SOURCES += [
         'D3D11SurfaceHolder.cpp',
diff --git a/dom/system/OSFileConstants.cpp b/dom/system/OSFileConstants.cpp
index 2b8a7e5369..551ed5773f 100644
--- a/dom/system/OSFileConstants.cpp
+++ b/dom/system/OSFileConstants.cpp
@@ -24,6 +24,10 @@
 #include <linux/fadvise.h>
 #endif // defined(XP_LINUX)
 
+#if defined(XP_MACOSX)
+#include "copyfile.h"
+#endif // defined(XP_MACOSX)
+
 #if defined(XP_WIN)
 #include <windows.h>
 #include <accctrl.h>
@@ -122,6 +126,22 @@ struct Paths {
   nsString winStartMenuProgsDir;
 #endif // defined(XP_WIN)
 
+#if defined(XP_MACOSX)
+  /**
+   * The user's Library directory.
+   */
+  nsString macUserLibDir;
+  /**
+   * The Application directory, that stores applications installed in the
+   * system.
+   */
+  nsString macLocalApplicationsDir;
+  /**
+   * The user's trash directory.
+   */
+  nsString macTrashDir;
+#endif // defined(XP_MACOSX)
+
   Paths()
   {
     libDir.SetIsVoid(true);
@@ -136,6 +156,12 @@ struct Paths {
     winAppDataDir.SetIsVoid(true);
     winStartMenuProgsDir.SetIsVoid(true);
 #endif // defined(XP_WIN)
+
+#if defined(XP_MACOSX)
+    macUserLibDir.SetIsVoid(true);
+    macLocalApplicationsDir.SetIsVoid(true);
+    macTrashDir.SetIsVoid(true);
+#endif // defined(XP_MACOSX)
   }
 };
 
@@ -280,6 +306,12 @@ nsresult InitOSFileConstants()
   GetPathToSpecialDir(NS_WIN_PROGRAMS_DIR, paths->winStartMenuProgsDir);
 #endif // defined(XP_WIN)
 
+#if defined(XP_MACOSX)
+  GetPathToSpecialDir(NS_MAC_USER_LIB_DIR, paths->macUserLibDir);
+  GetPathToSpecialDir(NS_OSX_LOCAL_APPLICATIONS_DIR, paths->macLocalApplicationsDir);
+  GetPathToSpecialDir(NS_MAC_TRASH_DIR, paths->macTrashDir);
+#endif // defined(XP_MACOSX)
+
   gPaths = paths.forget();
 
   // Get the umask from the system-info service.
@@ -933,12 +965,20 @@ bool DefineOSFileConstants(JSContext *cx, JS::Handle<JSObject*> global)
   // Note that we don't actually provide the full path, only the name of the
   // library, which is sufficient to link to the library using js-ctypes.
 
-  // On all supported platforms, libxul is a library "xul" with regular
+#if defined(XP_MACOSX)
+  // Under MacOS X, for some reason, libxul is called simply "XUL",
+  // and we need to provide the full path.
+  nsAutoString libxul;
+  libxul.Append(gPaths->libDir);
+  libxul.AppendLiteral("/XUL");
+#else
+  // On other platforms, libxul is a library "xul" with regular
   // library prefix/suffix.
   nsAutoString libxul;
   libxul.AppendLiteral(DLL_PREFIX);
   libxul.AppendLiteral("xul");
   libxul.AppendLiteral(DLL_SUFFIX);
+#endif // defined(XP_MACOSX)
 
   if (!SetStringProperty(cx, objPath, "libxul", libxul)) {
     return false;
@@ -986,6 +1026,20 @@ bool DefineOSFileConstants(JSContext *cx, JS::Handle<JSObject*> global)
   }
 #endif // defined(XP_WIN)
 
+#if defined(XP_MACOSX)
+  if (!SetStringProperty(cx, objPath, "macUserLibDir", gPaths->macUserLibDir)) {
+    return false;
+  }
+
+  if (!SetStringProperty(cx, objPath, "macLocalApplicationsDir", gPaths->macLocalApplicationsDir)) {
+    return false;
+  }
+
+  if (!SetStringProperty(cx, objPath, "macTrashDir", gPaths->macTrashDir)) {
+    return false;
+  }
+#endif // defined(XP_MACOSX)
+
   // sqlite3 is always a shared lib
   nsAutoString libsqlite3;
   libsqlite3.AppendLiteral(DLL_PREFIX);
diff --git a/dom/xbl/nsXBLPrototypeHandler.cpp b/dom/xbl/nsXBLPrototypeHandler.cpp
index 4872a850d7..963e6835c6 100644
--- a/dom/xbl/nsXBLPrototypeHandler.cpp
+++ b/dom/xbl/nsXBLPrototypeHandler.cpp
@@ -167,8 +167,13 @@ nsXBLPrototypeHandler::InitAccessKeys()
     return;
   }
 
-  // Compiled-in defaults, in case we can't get the pref
+  // Compiled-in defaults, in case we can't get the pref --
+  // mac doesn't have menu shortcuts, other platforms use alt.
+#ifdef XP_MACOSX
+  kMenuAccessKey = 0;
+#else
   kMenuAccessKey = nsIDOMKeyEvent::DOM_VK_ALT;
+#endif
 
   // Get the menu access key value from prefs, overriding the default:
   kMenuAccessKey =
diff --git a/dom/xul/nsXULElement.cpp b/dom/xul/nsXULElement.cpp
index 93d422d1e9..2ae03e0b17 100644
--- a/dom/xul/nsXULElement.cpp
+++ b/dom/xul/nsXULElement.cpp
@@ -523,6 +523,18 @@ nsXULElement::IsFocusableInternal(int32_t *aTabIndex, bool aWithMouse)
   // elements are not focusable by default
   bool shouldFocus = false;
 
+#ifdef XP_MACOSX
+  // on Mac, mouse interactions only focus the element if it's a list,
+  // or if it's a remote target, since the remote target must handle
+  // the focus.
+  if (aWithMouse &&
+      IsNonList(mNodeInfo) &&
+      !EventStateManager::IsRemoteTarget(this))
+  {
+    return false;
+  }
+#endif
+
   nsCOMPtr<nsIDOMXULControlElement> xulControl = do_QueryObject(this);
   if (xulControl) {
     // a disabled element cannot be focused and is not part of the tab order